# Automatic Movement of Rear Seat Headrest



## rljones (Jan 1, 2005)

*Rear headrest*

I have a 2004 Phaeton 5 seater. A rear seat headrest goes up when about 5 lbs is placed in that rear seat (or when a rear door is opened). Is there any way to keep the rear headrests down? Is this a VAG-COM coding thing?
Which brings up another problem I have. I'm a Mac person and it would seem that the VAG-COM solutions that I've read about on this site are only PC-based. Any Mac support known, or will dealers re-code certain items if asked?
Thanks, Robert


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## Paldi (Sep 4, 2004)

*Re: Rear headrest (rljones)*

The current wisdom says to pull the fuse on the headrests. Make sure it (the fuse) doesn't cut power to something important. I believe there's another thread below that gives the fuse number. Good luck!


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## rljones (Jan 1, 2005)

Fred,
You are correct: fuse 89 under driver's dash. Now headrests are stationary.
Thanks, Robert


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## PanEuropean (Nov 3, 2001)

*Re: Rear headrest (rljones)*

Robert:
When you next take your Phaeton in for service, be sure to let the technician know that you have intentionally removed the fuse. The Phaeton will generate and retain a fault code in non-vol vehicle memory indicating that the fuse is open-circuit, and when the tech polls the car for fault codes, he or she will see this code.
If you have not told the tech that you want the headrests depowered, it's a sure thing that the tech will install a new fuse.
Michael


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## jmdpjd1 (Aug 18, 2004)

*Re: Rear headrest (PanEuropean)*

Recoding for things by using their equipment is up to the dealer. I have found they will try if asked. Results have varied. 
My dealer thinks I am crazy for the things I want vagged on my Touareg. And he could not find a code to disable the head rest in my Phaeton but tried.


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## subsaharantribesman (Sep 23, 2003)

*Re: Rear headrest (rljones)*

Robert,
I'm very glad you have raised (so to speak) the question of the rear headrests. I, too, have a V8 5-seater, and had not experienced the phenomenon until this weekend, when I used a childseat for a grandbaby. Not only did the headrest rise, it began to go up and down uncontrollably. Very odd behavior. The manual addresses the issue of child seats, and here is where I feel really stupid.
Where is the seat adjustment located? There is none for the 5-seater, yes? So then why to the headrests have adjustment at all?
If this topic had been addresses in the FAQs, sorry for the repost (I searched and didn't find it)
Thanks and cheers,
Doug


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## rmg2 (Jan 23, 2004)

*Re: Rear headrest (subsaharantribesman)*


_Quote, originally posted by *subsaharantribesman* »_Robert,
I'm very glad you have raised (so to speak) the question of the rear headrests. I, too, have a V8 5-seater, and had not experienced the phenomenon until this weekend, when I used a childseat for a grandbaby. Not only did the headrest rise, it began to go up and down uncontrollably. Very odd behavior. The manual addresses the issue of child seats, and here is where I feel really stupid.
Where is the seat adjustment located? There is none for the 5-seater, yes? So then why to the headrests have adjustment at all?
If this topic had been addresses in the FAQs, sorry for the repost (I searched and didn't find it)
Thanks and cheers,
Doug

This may sound stupid but was the door closed and a child in the seat when the headrest went up and down uncontrollably?
I noticed that if the door is closed and the weight in near the front edge of the rear seat bottom cushion then the head rest remains in the lower position. However, if the weight slides to the mid to rear portion of the bottom seat cushion then the head rest moves to up position.
Is it possible that either the child in the rear seat is shifting their weight for and aft thus causing the headrest movement or without the child in the seat maybe the seat shifts upon accel and braking motion thus causing the headrest movement.
Just a thought.


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## rljones (Jan 1, 2005)

Doug,
The erratic headrest is probably the due to varying weight from the car seat. I noticed while cleaning the rear window that the headrests (with doors closed) went up and down as my weight shifted between the seats.
Unfortunately, I had to re-install the fuse for the rear seats as the car has the lumbar support/massage stuff in the rear and these are on the same circuit with the headrests.
My friend in Germany talked with his support person about this and she told him that this is only an issue with the US Market, probably due to litigation issues. However, for shorter people (such as my wife) when she sits in the rear seat the headrest is so high it doesn't serve much of a purpose. Also, when they're elevated rearward visibility is significantly reduced.
Robert


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## PanEuropean (Nov 3, 2001)

*Re: Rear headrest (subsaharantribesman)*

Doug:
As Rick pointed out, the rear seat headrests in the 5 seater don't have any adjustment at all - they will go up when the door is opened, and stay up when sufficient weight is detected on the seat, but we have no control over them.
The headrest rises when the rear door is opened to allow the driver to easily fit the tether strap for a child seat under the headrest. North American Phaetons have the 3 hooks on the hatshelf for the child seat tethers (you can thank the Canadian government for making that one mandatory, then the NHTSB picked up on it and thought it was a good idea...), European Phaetons don't have child seat tether hooks on the hatshelf unless you request them (a no-charge option).
The headrest will then stay up if 'sufficient' weight is detected on the seat, and the weight remains stationery - two characteristics that generally don't apply to the under 12 crowd. My experience is that the weight needs to be above about 70 pounds, but that is subjective, not a VW specification.
When I next pass through Europe (on my way back from Africa), I will be picking up some diagnostic scans of European Phaetons that my Zürich dealer is collecting for me. I'll look and see if there are any coding differences between the control modules for the European and North American car. To be honest, I kind of doubt there will be any difference - I think the European car behaves the same, headrest goes up with you open the door (just for flash, not for child seat installation), and stays up if there is sufficient weight present on the seat. But, we'll see.
Just for the record - the 4 seater cars give the rear seat passengers direct adjustment of the headreast height, on the 5 seater, they are either up or down, that's it.
Michael


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## Corradodrvrfnd (Feb 15, 2002)

*Re: Rear headrest (PanEuropean)*

my other question is are the rear airbags deployed only if the headrest is in the (up) seated position? It seems like that may be a possibility.


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## PanEuropean (Nov 3, 2001)

*Re: Rear headrest (Corradodrvrfnd)*

Very interesting question. I think the correlation would probably be "rear airbags are only deployed if weight is sensed in the rear seat", or, "rear airbags are only deployed if the rear seat belt is fastened", rather than correlating directly with the headrest position - but that is just a guess, not a fact.
I wonder if that information is in the owner manual, in that booklet about seat belts that none of us ever read?








Michael


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## subsaharantribesman (Sep 23, 2003)

*Re: Rear headrest (rljones)*

Thanks for all of the suggestions. In my own particular case, the child involved was approximately 34lbs. The erratic behavior of the headrest did not begin until I had removed the car and it was parked, engine off. He is, though, a squirmy little beastie and it's quite possible that he shifted his weight significantly back and forth while riding, thus confusing the poor Phaeton sensors. 
Michael is correct insofar as I neglected to read the manual entitled 2.1 Safety First. Unfortunately, though it does address child safety seats, it doesn't mention the headrests.
Ah well, another question for the dealer.
I hate to seem ghoulish, but are there any accident reports for Phaetons yet? The airbag system is pretty impressive (now that I've read the manual . . .), and I'm curious as to how well it works in real life.
Thanks,
Doug


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## Tail Spin (Oct 28, 2004)

*Re: Rear headrest (subsaharantribesman)*

I'll go one further on the head rests...
My son (7 years old) got his hand caught underneath the head rests as it was performing it's typical radical up and down dance with my son in the seat...activating and de-activating the weight sensor as he shifted sitting positions.
It was very scary for him as we discovered in the down position, significant pressure is applied by the head rest! Something that did not even occurr to me.
More importantly, are the airbags de-activated if I pull the fuse?!! 
Thanks Guys...you answer my questions before I even get to ask them!


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## PanEuropean (Nov 3, 2001)

*Re: Rear headrest (Tail Spin)*

Here is a picture of the switch that detects whether the rear seat is occupied or not. This switch is underneath the rear seat base, towards the back of the seat base. It is a very simple, straightforward micro-switch, which is actuated by pressure that is applied when weight is detected on the base of the seat.
When this switch is actuated, the corresponding rear headrest will rise and remain upright as long as weight is detected on the seat. The headrest will also rise when the corresponding rear door is opened, but that action is controlled independent of the seat occupancy sensor. The headrest rises when the rear door is opened to allow the driver to insert a tether strap for a child seat underneath the headrest, to connect it to the tether strap attachment point behind the headrest on the hatshelf. Three tether strap attachment points are provided as standard fitment on the hatshelf on all Phaetons shipped to North America. They can be retrofitted, by request, to Phaetons delivered elsewhere in the world.
The driver side rear seat occupancy sensor is switch G177 (found on VW wiring diagram 20, page 6), and the passenger side rear occupancy sensor is G178, found on page 13 of the same wiring diagram. Because VW is quite specific about using the words 'left' and 'right' elsewhere in this diagram, I suspect that the switch identification changes sides in right hand drive (e.g. UK or Singapore specification) vehicles, therefore, driver side means driver side, regardless of which side of the vehicle the steering wheel is installed on.
As far as I can determine from looking at the wiring diagram for the Rear Seats (diagram 20) and the wiring diagram for the Airbag System (diagram 12), there is no direct (analog) connection between the rear seat occupancy sensors and the airbag system. BUT - and this is a big but - there is a digital connection between the J522 Rear Memory Seat Control Module and the rest of the car, via the Comfort System CAN (Controller Area Network) bus. This can be seen on page 2 of wiring diagram 20. The J234 Airbag Control Module is connected to the Powertrain CAN bus, as seen on page 8 of diagram 12. The two CAN busses - Comfort and Powertrain - can exchange communications between each other via the J285 - Gateway in the control module with indicator unit in the instrument panel insert, which serves as a communications gateway (network hub) between the different CAN busses in the Phaeton. 
This means we cannot rule out the possibility that the igniters for the airbags in the outboard ends of the rear passenger seat backrest (igniters N201 and N202) , and the igniters for the seat belt tensioners on the rear outboard seats (igniters N196 and N197) may be affected by the rear seat occupancy sensors. In other words, if the occupancy sensor is disconnected, to stop the headrest from rising when someone sits in the seat, is is possible (not determined) that the side airbag igniter and the seat belt tensioner igniter for that seat may also be inactivated. There is just not enough information on the wiring diagrams for me to be able to make a call, one way or the other. The front passenger seat occupancy sensor IS part of the airbag circuit, meaning, it is shown on the airbag wiring diagram. So, that one is easy to call. The rear seat occupancy sensors are only shown on the rear power seat wiring diagram.
My personal guess - and, I stress this is a guess, not a fact - is that the status of the rear seat occupancy sensors will not affect the operation of the airbags. I make this guess because I think that anything that is important enough to relate to airbag control and operation would be made part of the (rather independent) airbag control system, which is fully documented on the airbag wiring diagram. But, it is up to each Phaeton owner to do his or her own due diligence before disconnecting the rear seat passenger occupancy sensor(s), to determine whether or not there are any unknown adverse effects or safety compromises that arise from disconnecting this sensor.
Michael
*Rear Seat Occupancy Sensor Switch*


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## dzier (Jun 19, 2004)

*Re: Rear headrest (rljones)*

I think it is cool when the headrests raise and lower.


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## PanEuropean (Nov 3, 2001)

*Re: Rear headrest (dzier)*


_Quote, originally posted by *dzier* »_I think it is cool when the headrests raise and lower. 

Agreed, I think it is a nice feature too. But, it can be frustrating for children and younger teens. If a child is close to the weight threshold that activates the switch, then the headrests tend to go up and down as the child moves around. For someone who is less than about 5' 9" in height, the headrests actually move up too high when they lift - they would be better off if the headrest didn't move up at all.
Michael


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## dcowan699 (Nov 22, 2004)

*Re: Rear headrest (PanEuropean)*

Even if the person is less that 5' 9", the back of the seat should suffice as a headrest regardless of how high the actual headrest is. So no matter the size of the person, they have head and neck proctection. The only problem I can fathom about the headrest issue (and it really doesn't bother me since I have parking sensors) is the inablility to see out of the back of the car.


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## whealy (Nov 15, 2004)

So perhapse the best solution would be to get into the seat and disconnect the head rest wire module?


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## PanEuropean (Nov 3, 2001)

*Re: (whealy)*


_Quote, originally posted by *whealy* »_So perhaps the best solution would be to get into the seat and disconnect the head rest wire module?

Only if you are satisfied, from doing your own due diligence, that disconnecting the seat occupancy sensor would not affect operation of the rear seat outboard airbag. That is the one unanswered question.
Michael


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## dcowan699 (Nov 22, 2004)

*Re: (PanEuropean)*

Will this triggle a fault code Michael?


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## PanEuropean (Nov 3, 2001)

*Re: (dcowan699)*

Hi David:
I'm not sure. If the switch is just a straightforward single pole, single throw switch - as it appears to be from the wiring diagram - then my guess is that if the switch is unplugged, then the electrical status would be no different than it is when the seat is unoccupied, meaning, the circuit would be open. But - again, just a guess. You could find out pretty easily by running a scan after the car has gone through a few operational cycles.
I am pretty sure that the operation of the upper air bag along the side of the car would be unaffected either way - that is a single airbag, so if it deploys, it deploys the full length of the car (see the Touareg photo below - only the driver seat was occupied when this accident took place). The part I am not sure about is deployment of the airbag at the outboard end of the rear seat backrest. I note that no such airbag deployed in the Touareg accident - but, whether this is because Touaregs don't have an airbag in that position, or whether it was because the rear seat was unoccupied (and thus the airbag did not fire), I don't know.
Michael
*Touareg Airbag deployment - only occupant in vehicle was the driver*


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## whealy (Nov 15, 2004)

*Re: (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_
Only if you are satisfied, from doing your own due diligence, that disconnecting the seat occupancy sensor would not affect operation of the rear seat outboard airbag. That is the one unanswered question.
Michael

Michael,
No, that wasn't what I was saying. I was thinking of simply disconnecting the "HEADREST" wiring harness, assuming there is one. Haven't looked it up as of yet. So it no longer received signals or had power to move. I would certianly not perscribe disconnecting the sensing switch that you have provided pics of. I do currently have my fues pulled to prevent their movement.


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## PanEuropean (Nov 3, 2001)

*Re: (whealy)*

Ah - sorry I misunderstood you. Your idea actually makes a great deal of sense - if it was possible to just disconnect the headrest motor, then the problem would be solved, provided you didn't need the headrest to go up when the rear door was opened, for the purpose of fitting a child seat tether underneath the headrest.
The only problem I can see with your idea is that the headrest motor does not have its own dedicated wiring connection. The power for the headrest motor comes from the J522 Rear Memory Seat Control Module via two connectors, the first is a 6 pin connector at the module itself, and then later on down the line, there is a 17 pin connector (wiring diagram 20, page 9, refers). If you disconnect either of these connectors, then you will lose a whole bunch of other services related to the seat, for example, control of the lumbar support, etc.
This kind of suggests that the only way to defeat the motor would be to cut one of the wires leading to the headrest motor.
I'll see if I can get a definitive answer to the question about whether the seat occupancy sensor has anything to do with the rear seat backrest airbag. Hopefully, it won't, and if that is the case, then just unplugging the occupancy sensor will be the simplest fix.
Michael


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## whealy (Nov 15, 2004)

Michael,
Additional info is always apprecaited.
As for the additinal services lost on the seat, I'm currently without those anyway from pulling the fuse. But I'd be game to cut a wire or two to get those functions back and still prevent the headrests from moving.


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## PanEuropean (Nov 3, 2001)

*Re: (whealy)*

I don't think you would be taking much of a risk if you cut a wire, even though that's the kind of thing I generally try to avoid based only on philosophical issues.
Would you like a copy of the wiring diagram? If so, send me an email - the diagram is too big to attach here on the forum.
Michael


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## whealy (Nov 15, 2004)

*Re: (PanEuropean)*

Yeah, I'm not much on just cutting wires either, but sometime you gotta do what you gotta do.
I beleive the wires in question are on pages 9 & 12 or wiring diagram 20 connected to a 6 & 18 pin connector (seems strange that the connectors are different) using a red/green and green/gray wire set.
If I'm not in the right place in the diagrams, just let me know. If I am in the right place, please thank the guy that taught me how to read these diagrams next time you see him ...


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## PanEuropean (Nov 3, 2001)

*Re: (whealy)*

I agree with you on the wire identification. 
For the left rear headrest, I would cut the wire on either track 109 or track 110. For the right rear headrest, I would cut the wire on either track 153 or 154.
I strongly suspect that the Phaeton will generate a fault code (two fault codes, actually - one for each side) once these wires are cut. I don't see this as being a problem at all, but you will want to advise the Phaeton tech at your dealership what you have done, otherwise, he or she will go in there and fix it for you.
Michael
PS: I don't know what the connector at the headrest motor looks like - the diagram suggests that there is a 4 pin connector there. What you could do, which would be a tad more 'mil-spec' than cutting the wire, is to release one of the pins from the connector using a special tool that is designed to release the pins from the connector, then just put a snippet of shrink-wrap over the exposed pin. This would allow you to return the vehicle to absolute OEM condition in the future, if you wanted to. You can buy such a special tool for releasing individual pins at most large automotive shops. I'll go digging for a picture of one, and post it, if I can find it.


_Modified by PanEuropean at 1:08 AM 6-8-2005_


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## PanEuropean (Nov 3, 2001)

*Re: (PanEuropean)*

Here's a picture of a generic pin removal tool. I think I bought this one at Pep Boys for about $6 or so a few years ago. It doesn't fit all VW pins, but it fits most. VW pins use only the two-prong design you can see on the left, not the circular design of the other 4 bits.
If you have a really sharp person in the parts department of your VW dealer, they can look up the connector in the electronic parts catalog (ETKA), and determine exactly the size of the pins in the connector from the information that appears there. Using that information, they can then tell you exactly what size of tool you will need to release an individual pin from the plug on the end of the connector, and pull it out the back of the connector. There is a good probability they might be willing to loan you the exact correct size tool to release the pin if you ask.
Michael
*Generic Pin Removal Tool*


_Modified by PanEuropean at 12:53 PM 11-1-2009_


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## whealy (Nov 15, 2004)

Hum ... I always thought this was called a Ninja dart wheel ...








As always, thanks for the info. I was thinking about the two wires. My assumption is that one may be dedicated to up movement of the rest while the other may be down. At least it seemed like a strange setup with the electric diagram of the movement component. Any thoughts.
As for getting to the control unit (I believe it's located behind the read arm rest cubby) or the restraint wire harness, both require rear seat removal from what I can tell. That's seating surface followed by seat backing. I've got a 5 seater which seems much simpler than the steps needed for the 4 seater. I'll probably hit the restraint end of the wiring, perhaps removing the harness at that point assuming there is one. I also probably won't work on this until a weekend given what all needs to be taken out ... and make sure my wife doesn't venture into the garage while I have the car apart!


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## whealy (Nov 15, 2004)

*Disconnection of rear seat headrest wire harness*

Well I finally took some time to attempt the disconnection of the rear seat head rest wire harness this weekend. I have a five seater which of course has different instructions than a four. But in order to the back surface of the rear seat, you must first remove the bottom surface.
Removal went off without a hitch. I actually didn't remove the bottom portion of the seat from the car. The connected wire harness for it had enough slack to allow removal of the back. Once the pieces were out, no problem disconnecting the rear headrest wire harness. But putting it all back together was a quite different story.
Getting the rear portion of the seat back on it's hooks proved to be very difficult. Part of it was learning. Part of it was the heavy piece being manipulate without assistance from someone else. Then there was the seat bottom. I had it out all weekend making multiple attempts to get it replaced. Finally after starting all this early Saturday morning, I got the bottom cushion back in place late tonight. Easily one of the more stressful "trim" mods I've ever done.
I also noticed while I had this all apart that my rear seat fans for seat cooling were not running. I checked with the vehicle running. This could play into this previous post Question on cooled seats. At least I know the rear isn't doing anything. My guess is the front isn't either. In any event, I'll be turning this issue over to service.
Some pics from my experience.
Headrest harness before removal








Headrest harness after removal









Seats being separated









Back of Back rear seat cushion









Back of passenger compartment without rear seat cushion removed. 








_URL Formatting edited, contents unchanged. Michael_


_Modified by PanEuropean at 5:46 AM 8-28-2005_


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (whealy)*

I'm interested in having this mod done on my 5 seater but am confused as to the actual method. There is discussion about cutting a particular wires as well as the (great) picture sequence where you show the "headrest harness" after removal (disconnection). 
Which is the method? Or is it either? I was going to have this done by an after-market electronics installer (along with a few other things) as I'm too chicken to mess with removing the rear seat myself. I may ask him to install a switch, if he can, that would toggle the function as I would prefer, for the obvious safety reasons, to have the headrest in the up position when tall people sit back there. It probably would be easier for him to do that using the "cut wire" solution if that is feasible. But that's up to him.


_Modified by car_guy at 3:33 PM 9-23-2005_


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

Hi Steven:
I am perplexed by your request - perhaps I am misunderstanding what you are trying to accomplish. I get the impression that you want to disconnect (or disable) the automatic up/down function, but you want the headrests to remain in the up (extended) position. I can't see what advantage this would provide, all I can see is disadvantages - the headrests will remain up when the rear seats are unoccupied, thus blocking your view out the back window when you use the inside rear view mirror.
What action is it that you want to eliminate? If you simply want to have both outboard rear seat headrests remain extended (up) at all times, I think the simplest way to go about that would be to open the two rear doors, then remove fuse 89. This will cut the power to the headrests, they will then stay up. If you later decide that you don't like things that way, you can replace the fuse - however, open both rear doors before you replace the fuse, so you don't have a surge of current going through the fuse when you are trying to re-seat it in the fuseblock.
Michael


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Michael,
No I want my cake...,etc. I definitely want the headrests down most of the time but would _like_ the ability to allow them to raise up when I so choose, i.e., when a tall person is sitting back there.
I thought one of the ways to disable the raising of the headrest was to cut a wire specified in the thread. If that is so, installing a switch would be, I would think, easy. Mounting the switch in a cosmetically acceptable way that would provide easy access would be more difficult. So my first choice is to 'disable' with a switch, my second would be to disable w/o a switch.
Regarding the removal of the fuse, I thought from the thread that this might have unintended negative consequences. Is that not so? If this is an acceptable solution, it would be entirely satisfactory. Inexpensive and relatively easy!


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

Hi Again Steven:
We never did figure out whether fuse 89 supplies power to anything other than the headrests, or whether the controller responsible for the headrests (probably the Central Comfort Controller, number 46) uses the same occupancy sensor on the seat that controls the headrests for the purpose of enabling or disabling rear seat passenger restraint systems (e.g. seatbelt tensioners) or occupant protection systems (e.g. side airbags).
But - if you want to keep the headrests down most of the time (in other words, over-ride the occupancy sensor) but still have the ability to raise them when you want to, the quick and dirty way to do this would be to put a SPST switch in the power supply that comes out of the back of the fuseblock, behind fuse 89. You'll have to do your own due diligence concerning the unanswered questions in the first paragraph. A somewhat more cautious - but much more complex - way of approaching it would be to put in a DPST switch that interrupts the power supply to the headrest motors, without affecting anything else on the fuse 89 circuit. That way, the occupancy sensor would still be powered, but the headrest motor would not respond if the switch was open.
Next time I get to the factory (hopefully in about 10 days, if my schedule does not change again), I will inquire if there is a way to turn off the headrest motors via soft-coding.
About your desire to be able to raise the rear seat headrests if you have tall occupants in the back seat - my own guess is that you would have to be hauling NBA players around before you would find a person tall enough to actually need the headrest lifted up. My own experience has been that even in the retracted position, the top of the headrest is way above the top of the head of an adult of average height. I guess this is a roundabout way of saying that I can understand why people with small kids want to disable the headrests - but, if you don't have small kids, why bother? (Forgive me if you do have small kids, and you mentioned it and I didn't notice it...







)
Michael


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_Hi Again Steven:
But - if you want to keep the headrests down most of the time (in other words, over-ride the occupancy sensor) but still have the ability to raise them when you want to, the quick and dirty way to do this would be to put a SPST switch in the power supply that comes out of the back of the fuseblock, behind fuse 89. You'll have to do your own due diligence concerning the unanswered questions in the first paragraph. A somewhat more cautious - but much more complex - way of approaching it would be to put in a DPST switch that interrupts the power supply to the headrest motors, without affecting anything else on the fuse 89 circuit. That way, the occupancy sensor would still be powered, but the headrest motor would not respond if the switch was open.
I guess this is a roundabout way of saying that I can understand why people with small kids want to disable the headrests - but, if you don't have small kids, why bother? (Forgive me if you do have small kids, and you mentioned it and I didn't notice it...







)
Michael

The first paragraph above describes exactly what I'm interested in doing. BTW, I do have two children, 9 and 13. It seems unnecessary to have restricted vision to the rear when the headrests in the up position don't give them any additional security. My wife finds that her head seems to fall in the space between the bottom of the headrest and the top of the seat when she is tired and tries to sleep back there.
I'm going to check the height of the headrests in the up position and see if I agree with you (I'm hoping that I do) that it is unlikely that taller passengers benefit with them in that position. I'd rather do something simple than something complex! In any case, I'm going to postpone the mods that I planned for next week until I hear of the results of your visit to the factory.
Let me say again how much I (and I think I can safely say we) appreciate all the help you give us. Our lives would be much more difficult (and boring) w/o your help. I'm sure we'd all like to chip in and get you that Cairo Grey model you have your heart set on. But, don't count on it!


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

Ah, the Cairo Grey one - I forgot about that one already. I just hope that they don't show me a 2007 Phaeton when I next visit Dresden. A friend of mine told me he had a surprise waiting for me, and my guess is that it is either a sneak peek at a 2007, or, one of those silver colour valve stem covers that we can't order through the dealer parts department. I am kind of hoping it will be the valve stem cover, that will have the least impact on my finances.
As for the headrests - *NOW *I understand why you want to do the modification... sorry I was so thick in the head before. Here's how I suggest you begin your research: Go to your VW dealer, and ask them to print you a copy of wiring diagram number 20 for the Phaeton - this is the diagram entitled "Rear power seats (with memory)". That is a seriously complex diagram. Have a look on page 20/9, tracks 109 and 110 - that appears to be the motor (V133) for the left headrest. The motor for the right headrest (V134) shows up on page 12, tracks 153 and 154. My *guess * - not fully researched - is that if you install your DPST switch so that it interrupts one side of the supply to each of those motors - for example, track 109 and track 153 - you will achieve your objective, without causing any adverse effects other than generating a fault code for each motor.
I don't know where the J522 Rear Memory Seat Control Module is located - hopefully it's not underneath the seat. If it is located under the hatshelf, where a whole bunch of other modules are, you could probably just install the switch on the drop-down panel that forms the ceiling of the forward part of the trunk. That way, it would be unobtrusive, but reasonably easy to get to - you just open the trunk lid, reach in, and flip the switch. But, again, I stress that you will have to do all the research yourself, I have just had a quick look at the wiring diagram.
Michael


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

OK, I'll get that diagram and give it to the installer. But I want to confirm two things. 
First, you refer to the "Rear power seats (with memory)" diagram, and I have a five seater w/o (rear) power seats or memory. Is this still the right diagram?
Second, are you still going to inquire at the factory about whether a software modification is available (see your previous post)? I just want to know if I should delay the work if a simpler non-intrusive solution may be available.
Thanks again.


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

I wasn't too sure about whether that wiring diagram applies to the cars without rear memory seats or not - however, I kind of suspect it does, because I cannot find any reference to headrest motors in the 'basic' wiring diagram (in other words, the wiring diagram that describes standard equipment only). There is no other supplementary wiring diagram for rear seats 'without' the memory function.
I will inquire at the factory, to find out if the rear seat headrests can be disabled via software coding. But, if the answer is yes, then this will mean that you will need to hook up a diagnostic scan tool to the car each time you want to disable or enable the headrest function. I'm not sure if that will meet your needs or not. If you would be satisfied with just turning the rear headrest lifting function off (for good) via software, assuming that is possible, then hang on for a couple of weeks until I get to Dresden.
BTW, I can't attach the wiring diagram here, because it is too large (one meg) to be attached. But, if you send me an email, I'll send the diagram to you via email.
Michael


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

I've sent the email.
If the headrests can be disabled by software coding, I'll just do that and be satisfied. I have a contact with a VAG-COM. So, I'll wait until you've made your visit before making any changes.


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Michael,
Did you get a chance to inquire at the factory about software disabling of the headrests? Thanks


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

Hi Steven:
I didn't get up to Dresden as planned on this visit. I'm going to try to go there the first week of November.
Michael


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## Rowayton (May 29, 2004)

*Re: (PanEuropean)*

If you put accesable inline switchs on the package shelf to each motor would you not in effect have the best of both worlds? You are still fused and you can stop the motor at a head rest height you like. With no childern as passengers the system would funtion as VW designed it and no fault code should register. In effect, you have a reversable "cut" in a fused system.
RB


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## car_guy (Aug 19, 2005)

*Re: (Rowayton)*

The installation of a switch for each headrest was the approach I was considering if I couldn't disable the movement by simple software coding. However, this may have to be done carefully regarding the placing of the switches. 
Remember that the headrest rises as soon as you open the rear passenger door. It is then probably too late to flip the switch as that would only keep the headrest in the up position, even when you leave the car! So the switch needs to be flipped prior to opening the rear door on the side you are trying to control. This is certainly not an insurmountable problem, just one that has to be taken into consideration. 
So I'm going to let my professional installer take a stab at this when he installs my laser jammer. He's already hardwired my Valentine 1 and glued in my EZ-Pass transponder behind a lower grill (using removable silastic sealant) at a very reasonable cost.


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## Rowayton (May 29, 2004)

*Re: (car_guy)*

Steve,
Two work arounds possible. Activate the switch through an open window or have someone kneel on the floor to flip switchs at the height you want as the door is being opened?
RB


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## Paldi (Sep 4, 2004)

*Re: (Rowayton)*

As I recall, the 4-seat option has headrests that are controllable via a pair of switches. If true, any chance you can use that setup on a 5-seat?


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## car_guy (Aug 19, 2005)

*Re: (Rowayton)*

I don't think it's a big problem. It can be solved by putting both switches where they can be reached from both rear seats, or perhaps someone in the front. This way a person gets in the back, flips the switch for the 'other' rear seat headrest before it goes up. The passenger can then slide over and repeat the process if necessary.
Most of this is academic as the headrest will be left in the down position 99% of the time.


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## car_guy (Aug 19, 2005)

*Re: (Paldi)*

I would like that if the implementation is not too complex, but I'm not sure it's necessary. A simple switch toggling the auto-up behavior would be fine. I don't need more granularity than completely up and completely down.


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## copernicus0001 (Nov 30, 2004)

*Re: (car_guy)*

What about taking a look at how the front headrests are controlled. If you can determine that, you may be able to apply the same control to the rear headrests.


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

I asked the engineers in Dresden if there was any way to disable the automatic up movement of the rear seat headrests on a 5 seater Phaeton when either a rear door is opened, or weight is detected on the rear seats. The answer is no, there is no way to do this via software coding.
I then told them that some owners (those with small children) had disabled the rear seat headrests by disconnecting the weight-sensing switch under the seat, but that we were concerned that this might have some effect on the occupant protection system - meaning, whether or not the rear seat side air bags deploy in the event of a side impact collision.
They will investigate whether the rear seat occupancy sensor switch - the one that controls the headrests - is used for any purpose by the occupant protection system, and get back to us. The general consensus was that no-one thought that the airbag system used that information, but they want to be 100% sure, not just 99.9% sure.
Michael


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## pretendcto (Nov 23, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Hi, I've had my Phaeton for a few days now and I am also interested in somehow controlling the automatic rear headrests. My 5 year old son triggers the headrest but his head is not even close to it. It is annoying to have the obstruction in the rear window. Any further thoughts on the best practice for this 'mod'? Thank you!


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (pretendcto)*

Hi Paul:
We can't really 'control' it, other than disconnecting the wire that leads from the weight-sensor underneath the seat, as William did on his car (see the bottom of the first page of this post for the details).
I'll take a look at the wiring diagrams later tonight, and see if there is an easier way to get access to that wire - some way that does not involve removing the seat base. If I find anything, I'll post it here for you.
Michael


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## pretendcto (Nov 23, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Michael,
You are an amazing moderator for this forum and I truly appreciate your unbelievable commitment to this awesome car. I'm a hardcore DIY (like you seem to be) and this forum has given me enough information to comfortably purchase a Phaeton over a more 'mainstream' car. My 2 day old loaded Silver V8 is working out great so far ....
Thank you!!!!
Paul


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (pretendcto)*

Hi Paul:
Thanks for your kind words. I really didn't buy the Phaeton to drive it (though I do take it to GTG's from time to time) - I mostly bought it so I could take it apart and admire the craftsmanship - not to mention play with it, too.








I have always found the forum to be a friendly and fun place to exchange information, and I have learned a great deal from all the other members here.
Michael


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## chrisj428 (Feb 26, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Michael, 
I just want to echo everyone else's accolades and thank you for your unending dedication to the Forum. This is the first on-line community of which I've been a part and would not have done so if it weren't for your organizational and diplomatic skills. In fact, I probably wouldn't be nearly as involved with the Phaeton as I am if it weren't for this corner of Vortex and while my bank account will surely curse you come next month, the rest of me offers a heartfelt "Thank You!"


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (pretendcto)*

Hi Paul:
Here's the info I promised earlier.
I had a look at the wiring diagram for the rear seats, and I really can't see a better or easier way than what has already been discussed to solve the problem of headrest operation with children in the back of the car.
I think that what we have discussed in this two page thread pretty much boils down to two options:
*1) Remove fuse 89 from the front fuse panel*
This is a simple action to take, and it is easy to reconfigure the car back to normal operation if you want. The only disadvantage to removing fuse 89 is that you will also lose the heat, ventilation, memory, and massage functions from the two rear seats, although I don't think that would be any great loss for your 5 year old... he's probably sitting in a child-bucket anyway, and thus unable to make use of these features.
Fuse 89 is really easy to find, it is in the very bottom inboard corner of the fuse panel - see page 74 of the Owner Manual booklet 3.2 (Tips and Advice) for an illustration of the fuse panel, and instructions explaining how to open it.
*2) Disconnect the cable harness from the rear seat headrest motor*
This approach requires more work, but it leaves the other features of the rear seat (heat, massage, etc.) still operational. This is what William did with his Phaeton - he documented the procedure very well on the first page of this thread. The only disadvantage of doing this is that it will not be quick or easy to re-enable that headrest if you need to carry an adult passenger in your car.
I think that if I was in a similar circumstance - I frequently carried a child in the back seat - I would probably pull the fuse. The kid won't miss the other features of the rear seat, and I could easily re-enable all those features if I wanted just by replacing the fuse. BTW, if you do choose to remove the fuse, let your Phaeton tech know about it, next time you take the car in for service. The missing fuse will show up as a fault on the diagnostic scan that is always done when the car comes in for service, and the tech will probably replace it for you if he or she is unaware you deliberately took it out.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

Ah - one more thing: The engineers from Dresden got back to me with an answer to our question about whether the rear seat occupancy sensor has anything to do with the occupant protection system (the side airbags, or the seat belt tensioners) - the answer is NO, there is no information passed between the rear seat occupancy sensor and the airbags or seat belt tensioners.
In other words, we can pull the fuse or disconnect the headrest electrical plug, and the only impact of doing this will be what is obvious to us - the rear seat comfort functions won't work if the fuse is pulled, or the headrest will not move up and down if the electrical connector to it is disconnected.
Michael


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## pretendcto (Nov 23, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*

I've had the car for a little over 3 weeks now and the rear headrests rising automatically is the only thing that's annoying about the car. I guess I'll disconnect the wiring from the rear headrest motors unless somebody advises against it ...
whealy, have you been happy with this mod? Your feedback is appreciated!
Thanks, Paul


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_
In other words, we can pull the fuse or disconnect the headrest electrical plug, and the only impact of doing this will be what is obvious to us - the rear seat comfort functions won't work if the fuse is pulled, or the headrest will not move up and down if the electrical connector to it is disconnected.
Michael

Michael, do you want to amend this in light of your discovery of how the rear seat occupancy sensors affects the rear heating system? BTW, feel free to delete this post.


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## car_guy (Aug 19, 2005)

*Re: Disconnection of rear seat headrest wire harness (pretendcto)*


_Quote, originally posted by *pretendcto* »_I've had the car for a little over 3 weeks now and the rear headrests rising automatically is the only thing that's annoying about the car. 

Well, if that's the only thing that bothers you, it certainly says a lot of good things about the car! 
BTW, it annoys my family as well as it raises the headrests too high for my wife or kids.


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## pretendcto (Nov 23, 2005)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*

Yes, that's the only annoyance so far ... it's rather comical to see my wife and/or kids with the headrest way above their heads. I should clarify that it's only a nit-pick and that the car has exceeded every expectation!


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## PanEuropean (Nov 3, 2001)

*Re: Disconnection of rear seat headrest wire harness (car_guy)*


_Quote, originally posted by *car_guy* »_Michael, do you want to amend this in light of your discovery of how the rear seat occupancy sensors affects the rear heating system? 

Hi Steven:
Yes, that's a good idea, thanks for suggesting it. The folks in Dresden only looked at 'safety and security' systems with respect to the disconnection of the switch. The truth is, because all the controllers in the car (between 40 and 70 of them, depending on configuration) are networked, *ANY *controller can poll any other controller for information if it wants it. There's no way to identify what controller is doing the polling unless you get into some serious electronic engineering, for example, packet sniffing on the three CAN networks (drivetrain, infotainment, and comfort).
Getting back to your original point - we discovered from research done in this post: Climatronic Control Problems that the Climatronic Controller, or HVAC controller, polls the rear seat occupancy sensors to determine if it makes sense to turn on the electrically powered supplemental footwell heaters that serve the rear seat footwells.
The rear seat footwells are heated by air that is warmed by passing over the heater core and is then routed through ducting to the rear of the car. If the engine coolant has not reached full temperature, it will take a little while before the air coming out the floor vents at the front of the rear seat footwells is warm. If the rear seats are occupied (as detected by the occupancy sensors), then the supplemental electric heaters will be turned on to provide immediate heat so that the rear seat occupants don't have to wait for the engine to reach full temperature.
Also, if the rear seat passengers ask for a higher temperature in their quadrant of the car than the same side front passenger, the only way to provide additional heat to the rear (without cooking the front person) is to heat the air electrically right at the rear seat outlet. To minimize electrical loads on the car, these rear seat electrical heaters are disabled if the rear seats are not occupied.
I think that kids usually jump and squirm around enough to generate whatever heat they need themselves...
Michael
*4 Zone Climatronic Controller Network Topology*


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## iholtzman (Dec 3, 2005)

*Rear Headrests How do they go up and down?*

I have a 2005 Phaeton with electric headrests. How do I control them the pictures in the owners manual don't seem to match. Also when I'm driving the rear passenger head rest goes up and down by itself. I think it only happens when my son is sitting in the center of the rear seat. I've also noticed it goes up when I open the rear door. Are their sensors in the seat. Any explanation would be appreciated.
Thanks
Ira Holtzman


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## murphybaileysam (Dec 29, 2005)

Ira;
Look at the thread in the table of contents that is "Questions new Owners have asked". It has the topic of "Rear Headrest- What makes them go up and down" that should explain everything to you. That whole table of contents covers about everything that you would need to know, (and some things that you don't!)
I'm around The Glen quite often so I'll keep an eye out for you!


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## PanEuropean (Nov 3, 2001)

*Re: Rear Headrests How do they go up and down? (iholtzman)*

Hi Ira:
I merged your question onto the end of the existing post that deals with it (the one Jay referred to).
Michael


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## PanEuropean (Nov 3, 2001)

*Re: Rear Headrests How do they go up and down? (PanEuropean)*

I finally got to the bottom of the question "Why do the rear seat headrests rise up when the rear doors are opened?" I think most of us know the logical answer - it is to provide clearance underneath the headrest so that a tether for a child seat can be installed.
However, there is a technical (configuration) answer as well, and this has to do with whether or not the Phaeton is equipped with clips on the hatshelf that accept an upper tether strap for a child seat. All North American Phaetons have these clips, which are identified on the build sticker as production code *3B1* or *3B3*. If a Phaeton is built without these additional anchors on the hatshelf (production code *3B0*), then the rear seat headrests will not rise up when the door is opened - they will only rise up when sufficient weight is applied to the base of the seat.
The coding (programming) of this is done at the byte level within the central comfort controller (controller 46). We as end users cannot change byte level coding with a VAS 5052 or a VAG-COM. Byte level coding within this same controller also determines whether the windows and sunroof can be opened or closed via the key fob or keyless access door locking button, and whether the two exterior mirrors adjust synchronously when the mirror switch is in the 'left' position or not.
Michael
*Supplemental Child Seat Tethers*
Required by law in some markets, available by request in others.


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## Jim Morris (Nov 8, 2008)

I have a question regarding the automatic rear seat headrest movement: I've got a 5-seater with only rear seat heating (no memory or cooling/massage function) and my headrests have never moved an inch. Are these automatic headrests only installed on Phaetons with rear seat memory or has the previous owner of my car already disabled them? I expect I do have the occupancy sensors as my car did have the rear climate control panel installed so I probably have the electrical heaters in the footwell.


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## Victor R (Jan 7, 2010)

Jim, 

I'm glad you revived this thread. While I don't have an answer for you, hopefully others will. 

I read this thread some time back, and the rear headrest automatically rising in the five-seater continues to be a vexing issue. My wife finds the back seat very uncomfortable for this reason - the headrest is just right for her at the bottom position, but, when raised, hits her head at the wrong spot. (I have not seen this term used on this forum, but, when looking at audio-video equipment, the term "WAF" -wife approval factor - is often a crucial determinant as to whether or not one should purchase a component.) (In fact, the WAF on the Phaeton is what allowed me to purchase the four-seater, as the rear headrests in those are user-adjustable.) 

I considered removing the fuse as was discussed at the beginning of this thread, but still don't have a handle on whether doing this affects airbags or not. Has anyone been able to ascertain this in the five years since this thread was originally active? 

Victor


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## 53 0val (Feb 23, 2010)

Victor, 

Look at Michael's post on 12/14/05. I think that's the answer you are seeking. 

Bob


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## PanEuropean (Nov 3, 2001)

Victor R said:


> I considered removing the fuse as was discussed at the beginning of this thread, but still don't have a handle on whether doing this affects airbags or not.


 To the best of my knowledge, there is no connection (logic or electrical) between the power supply for the rear headrests and the airbag system.

The fuse protects the power supply to the motors that operate the headrest. I don't believe it has any effect on the sensor that detects whether or not anyone is in the seat. It is possible that the seat belt pre-tensioners for the rear seats may not fire if the seat is deemed to be unoccupied, but again, occupancy determination is done by the load sensor in the seat base, not by the position of the headrest - which is also determined by the load sensor in the seat base.

Furthermore, I don't believe that the airbag system itself (setting aside the seat belt pre-tensioner) considers whether or not rear seats are occupied. If it did, then the airbag system would be obliged to post a warning message in the instrument cluster if there was any loss of integrity as a result of the rear seat headrests not being powered.

You could verify whether or not the rear seat occupancy sensor is affected by fuse pulling by opening controller 46 (central comfort), finding the measured value block that detects rear seat occupancy based on weight applied to the seat base, and determining if that discrete still changes state after the fuse for the headrest motors has been pulled.

Michael


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## Jim Morris (Nov 8, 2008)

Michael, do you know if all Phaetons have the motorized rear headrests or only the ones equipped with rear seat memory?


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## PanEuropean (Nov 3, 2001)

Hello Jim:

To the best of my knowledge, all cars had them, but there might be low-end interior options that were offered in Europe that I am not aware of.

Michael


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## Jim Morris (Nov 8, 2008)

Thanks, what would be the best way for me to find out without having to remove the entire back seat?


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## PanEuropean (Nov 3, 2001)

Uh, open the rear door, and see if the headrest goes up?

or, 

With the engine running, sit in the rear seat, close the door, and see if the headrest goes up?

There is a possibility that the headrest only rises when the door is opened on North American specification cars, this to enable the driver to fit the top tether cord of a child seat underneath the headrest. But, if you actually put an adult into a rear seat and close the door (assuming the engine is running), the headrest should rise up if the vehicle is equipped with power rear seat headrests.

Michael


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## Jim Morris (Nov 8, 2008)

Hi Michael, 

I think you misunderstood me (see my original question a few posts back), my headrests have never moved, but as I'm the second owner of my vehicle, it could be that the previous owner had the motors disconnected. My front seats have manual headrests, but they have a 'button' on the side of one of the openings to 'release' the headrests if you want to lower them. The rear headrests don't, and moving them up and down by hand there is a lot more 'resistance' compared to the front ones. So I was just wondering if my headrests have been automatic all along, but have been disconnected previous to my ownership.


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## PanEuropean (Nov 3, 2001)

Jim:

I am going to guess that if your front seat headrests are not motorized, then the back ones probably are not either.

You might be able to find a more definitive clue by comparing the build sticker in the spare tire well of your car (also found in the owner manual) to the decoding information at this post: Understanding Phaeton Production Codes & Build Stickers (downloadable PDF).

Another thought would be to look and see if there is a fuse in the position used for the rear seat headrests. VW normally does not put fuses in slots that are not used. If there is no fuse, try putting one of the correct size in that slot (to rule out the possibility that it was there originally and was removed) - if nothing happens, then you probably don't have that feature. Don't forget to remove the unused (and unwanted) fuse.

Finally, you could look at measured value blocks within Controller 46 (and/or controller 66) to see if you are getting any kind of discrete signal from the occupancy sensor in the rear seat bases that controls operation of the rear seat headrests. Controller 66 is the rear seat controller. If you don't have a controller 66 in your car, then I think that is a pretty strong hint.

Michael


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## Jim Morris (Nov 8, 2008)

Hi Michael, 

Thanks for your answers. 

The production code list of my particular Phaeton is: http://morrisj.im/buildsticker.php but the only thing it has to say about the rear seats is "Rear seat bench/backrest, unfolding". 

I've tried accessing controller 66 but it isn't responding, probably since it's not there as I don't have any 'intelligence' in the rear seat (only two-zone heating). Controller 46 doesn't have any MVB for the occupancy sensors as far as I can tell, and neither does the airbag controller. 

What's strange, though, is that I do have a fuse in position 89 (a number 15 fuse, to be exact). But maybe it's there for the rear seat heating? 

Jim


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## Victor R (Jan 7, 2010)

Well, 

I took the plunge and removed fuse 89 based on Michael's response. So far so good: headrests remain down, WAF is up, life is good. 

I'll be taking the car out for a longer drive today - I'll let you know if the seat seater still works without the fuse. 

Jim - one easy thing to check - is the your fuse 89 good? I could envision someone putting a blown fuse in there if they don't want the function and want to have others keep their fingers off of it. 

Victor


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## Jim Morris (Nov 8, 2008)

Victor R said:


> Jim - one easy thing to check - is the your fuse 89 good? I could envision someone putting a blown fuse in there if they don't want the function and want to have others keep their fingers off of it.


 Thanks for your suggestion, I checked and fuse 89 is A-OK in my car. Maybe there is more connected to that fuse than only the headrest motors?


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## Victor R (Jan 7, 2010)

It seems like the rear seat warmers are on that fuse as well. So the trade-off for now looks like no movement, no heat. (WAF is down, but not as low as it was when the headrests went up...)

The nice thing though is I can always put the fuse back in...

Victor


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## PanEuropean (Nov 3, 2001)

Photos re-hosted.

Michael


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## maccd87 (Dec 20, 2015)

Bumping this thread for a part number and information on the seat occupancy sensor. My headrests do not remain in the up position after the rear door is closed (and I'm in the seat). The rear seat coolers/heaters are not functioning and I believe this is the cause.

What is the part number for the rear seat occupancy sensor (G452 in the wiring diagram)? Is it anything more than a microswitch?

Which measurement blocks in the 66 controller indicate that sensor?


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