# auxilliary heater



## stefanuk (Jul 7, 2010)

Hi All,

I wonder if anyone can help as i'm having problems with my auxilliary heater.
When i scan the car i cannot access controller 18, and the scan keeps bringing me back to the radio/navigation not being able to access the controller and i cannot access it with VAG-COM.i know the heater is working as i see the exhaust fume from the front of the car where it sits so i know that's ok.
Does anyone know where the controller for the heater is? i'm hoping that i don't need to replace the whole RNS 810 unit and can get away with just replacing the motherboard.
On my screen i see the options to start the heater immediately or set a time to start but when i press either option there is a whirring from inside the RNS but nothing else.

Thanks,
Stefan


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## Gabs08PHTN (Jan 6, 2011)

Hi Stefan,
The auxiliary heater control unit is located at the heater itself. 
If I was you, I would first unplug fuse #16 at the dash panel fuse holder, that is the auxiliary heater control unit fuse, for a few seconds in order to reset it. Then try to access the controller with VagCom, but rather than on the general gateway controller list, select it straight away from the control unit screen.
I hope it helps.

Gabriel


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## stefanuk (Jul 7, 2010)

Hi Gabriel,


Thanks for that, i'll try that when i have some daylight.
The heater itself was replaced under warranty last week so the controller must be ok if it's attached to the heater itself.i know there was a problem with the heater as the coolant temperature sensor was showing as defective when scanned. Now the car will heat up a lot quicker than it was. I just can't access the parking heater. Hopefully removing the fuse and replacing will help.


Regards,
Stefan


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## stefanuk (Jul 7, 2010)

Hi Gabriel,


Managed to try your suggestin today Gabriel but no joy. Removed the fuse and replaced but still not able to access controller 18.
I noticed today that i get what i can only describe as a chirping noise coming from somewhere behind the dash, it's louder or quieter dependant on fan speed. 
I wonder if this has something to do with the problem. I'm not sure what's causing the noise as my scan shows nothing other than not able to access controller 18. Could it be something within the HVAC?

Regards,
Stefan


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## Gabs08PHTN (Jan 6, 2011)

Hi Stefan,
What a pity!
With regards to the chirping noise the old ZAB units featured a small cooling fan, and I guess that so the new RNS units do. Could that be the source of the chirping noise? What do you reckon?
I am wondering if the reason why you cannot access the auxiliary heater controller is because the gateway controller is not coded properly and therefore it does not know that the heater is there.
If I recall it correctly, (please correct me if I am wrong) when you access the gateway controller using VCDS, there is a button on the screen that says something like "Gateway Installation List". If you click on it, a list showing all the control units of your Phaeton is displayed. Next to each control unit there is a tick box. Check whether the auxiliary heater is ticked or not.
Before you tick any boxes, I would sugest to return to the Gateway main window, click on coding and copy down the code (Just in case you need to recode it later...). Then open the controller list and tick the Auxiliary heater box in case it was not ticked. Return to the Gateway main window, click again on coding and check if the code has changed. Copy that new code down too. Exit VCDS, re-open it and check whether you can access #18 controller now.
However, if you do not feel comfortable fiddling around with VCDS, or in case any of my instructions was wrong, please do not make any changes, report back and we will keep on investigating .

Gabriel


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## stefanuk (Jul 7, 2010)

Hmm..........well i looked into the gateway list as you suggested Gabriel but i don't see any tick boxes. However it tells me controller 18 is not accessible. Scan tells me controller 18 is not responding. I'm a little confused as this is a new heater.
I've tried the fuse out trick again but no joy.
The chirping sound is not there when the car is cold and the fan on full for defrost etc. It only starts to 'chirp' when the car is getting up to temperature. It is also very dependent on the fan speed, lower fan speed and less 'chirping'. The outside temperature seems to have an effect too as today was quite mild and there was no chirping. Could this be due to the aux heater not being needed so much.
I'll post my scan at some point as that may help pin down the problem.


Regards,
Stefan


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## Gabs08PHTN (Jan 6, 2011)

Hi again Stefan,
I run a VCDS scan to my Phaeton today and if I log onto controller 19, that is the CAN Gateway, I can see a button on the VCDS screen that states "Installation List". If I press it, a long list with all the Phaeton controller pops up, and nex to each controller there is a tick box. However only those control units installed in my Phaeton are ticked. Also, to my surprise, Controller 18, that is the auxiliary heater, is not there... So wrong guess...
When I operate the auxiliary heater, more often than not, I can hear a "clicking" sound coming from the rear (That is the fuel pump that feeds the burner), but I do not listen to any sounds coming from behind the dash.
The fact that VCDS cannot access the controller is quite odd. Was the replacement part identical to the original one? I mean, do both of them share the same part number?

Gabriel


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## stefanuk (Jul 7, 2010)

Here is my scan, if you ignore the DTC that relate to the lights as they only appeared following removal and replacement of the front bumper, otherwise it;s the same scan before replacement of the auxilliary heater.


VIN: WVWZZZ3DZA8001899 License Plate: FD59KXN
Mileage: 84770km-52673mi Repair Order: 



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: 3D (6N0)
Scan: 01 02 03 05 06 07 08 09 15 16 17 18 19 34 36 37 38 42 46 47
52 55 56 62 65 68 71 72 76 77

VIN: WVWZZZ3DZA8001899 Mileage: 84770km-52673miles

01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
05-Acc/Start Auth. -- Status: OK 0000
06-Seat Mem. Pass -- Status: OK 0000
07-Control Head -- Status: OK 0000
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: Malfunction 0010
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: Malfunction 0010
18-Aux. Heat -- Status: Cannot be reached 1100
19-CAN Gateway -- Status: Malfunction 0010
34-Level Control -- Status: OK 0000
36-Seat Mem. Drvr -- Status: OK 0000
37-Navigation -- Status: Malfunction 0010
38-Roof Electronics -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
46-Central Conv. -- Status: OK 0000
47-Sound System -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: Malfunction 0010
62-Door, Rear Left -- Status: OK 0000
65-Tire Pressure -- Status: OK 0000
68-Wiper Electr. -- Status: OK 0000
71-Battery Charger -- Status: OK 0000
72-Door, Rear Right -- Status: Malfunction 0010
76-Park Assist -- Status: OK 0000
77-Telephone -- Status: OK 0000

-------------------------------------------------------------------------------
Address 01: Engine (CEX) Labels: None
Part No SW: 3D0 907 401 G HW: 3D0 907 401 D
Component: 3.0TDI EDC17G000AG 0030 
Revision: --H02--- Serial number: VWX3Z0I3884684
Coding: 0406002C191F0160
Shop #: WSC 01065 000 00000
VCID: 2343D257E1972539529-513C

No fault code found.
Readiness: 0 0 0 0 0 

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 09L-927-760.lbl
Part No SW: 09L 927 760 R HW: GS1 9.1 1.4 
Component: AG6 09L 3,0 TDI RdW 3606 
Revision: --H04--- Serial number: 4539742
Coding: 0000001
Shop #: WSC 01065 000 00000
VCID: 46856BC332E53011157-515A

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 3D0-614-517.lbl
Part No: 3D0 614 517 AK
Component: ESP 5.7 allrad H35 0047 
Coding: 0008356
Shop #: WSC 01065 000 00000
VCID: 6BD3FA7749C72D79AA9-513C

No fault code found.

-------------------------------------------------------------------------------
Address 05: Acc/Start Auth. Labels: 3D0-909-13x-05.lbl
Part No SW: 3D0 909 137 F HW: 3D0 909 137 F
Component: Kessy 6850 
Revision: 00H22072 Serial number: VWX3Z0I3884684
Coding: 0151788
Shop #: WSC 01065 000 00000
VCID: 2A5D3F7381BDF47111F-807F

Subsystem 1 - Part No: XXXXXXXXXXX 
Component: ELV XXXX

No fault code found.

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Address 06: Seat Mem. Pass Labels: 3D0-959-759.lbl
Part No: 3D0 959 759 CA
Component: Sitzmemory D1 BF 1722 
Coding: 0000003
Shop #: WSC 01065 000 00000
VCID: 77FBD607028F99995E1-8022

No fault code found.

-------------------------------------------------------------------------------
Address 07: Control Head Labels: 3D0-907-048.clb
Part No SW: 3D0 907 048 HW: 3D0 907 048 
Component: J127 KBT vorn 0031 
Revision: ABH10001 Serial number: VWZ6Z7J0299011
Shop #: WSC 00000 000 00000
VCID: 63C39257A6176539129-8036

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 3D0-907-040.lbl
Part No: 3D0 907 040 L
Component: Climatronic D1 2037 
Coding: 0000001
Shop #: WSC 01065 000 00000
VCID: 275BC64792AFC9190E1-8072

2 Faults Found:
00779 - Outside Air Temp Sensor (G17) 
010 - Open or Short to Plus - Intermittent
01341 - Control Module in Instrument Panel On Comfort CAN (J285) 
008 - Implausible Signal

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Address 09: Cent. Elect. Labels: 3D0-937-049-V2.clb
Part No SW: 3D0 937 049 N HW: 3D0 937 049 N
Component: J519 6900 
Revision: -4005--- Serial number: --------------
Coding: 618C0000AB2115860100000000000000
Shop #: WSC 01065 000 00000
VCID: 35671C0F5803AB898CD-8060

4 Faults Found:
01493 - Bulb for Blinkers; Front Left (M5) 
011 - Open Circuit - Intermittent
02498 - Left Low Beam Reflector Motor (V294) 
011 - Open Circuit - Intermittent
01496 - Bulb for Fog-Lamps; Left (L22) 
011 - Open Circuit - Intermittent
01500 - Bulb for Fog-Lamps; Right (L23) 
011 - Open Circuit - Intermittent

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Address 15: Airbags Labels: 3D0-909-601.lbl
Part No: 3D0 909 601 E
Component: 0H Airbag 8.4E+ H12 0935 
Coding: 0012360
Shop #: WSC 01065 000 00000
VCID: 2547CC4FE8A3DB093CD-8070

No fault code found.

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Address 16: Steering wheel Labels: 7L6-953-549.lbl
Part No: 7L6 953 549 L
Component: J527 3601 
Coding: 0000212
Shop #: WSC 01065 000 00000
VCID: 489965FB3FF12661E7B-801D

No fault code found.

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Address 17: Instruments Labels: 3D0-920-xxx-17.lbl
Part No SW: 3D0 920 983 C HW: 3D0 920 983 C
Component: J285 KOMBI-INST. 0616 
Revision: KPH06V01 
Coding: 0039401
Shop #: WSC 26222 001 1048576
VCID: 295FC07F80BBFF69185-807C

2 Faults Found:
01207 - Control Module for Auxiliary Heater (J364) 
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 1
Reset counter: 149
Mileage: 83912 km
Time Indication: 0
Date: 2014.12.03
Time: 14:21:48

01320 - Control Module for Climatronic (J255) 
013 - Check DTC Memory - Intermittent
Freeze Frame:
Fault Status: 00101101
Fault Priority: 2
Fault Frequency: 1
Reset counter: 211
Mileage: 84662 km
Time Indication: 0
Date: 2014.12.23
Time: 09:32:22


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Address 17: Instruments Labels: 3D0-920-xxx-17.lbl
Part No SW: 3D0 920 983 C HW: 3D0 920 983 C
Component: J285 KOMBI-INST. 0616 
Revision: KPH06V01 
Coding: 0039401
Shop #: WSC 26222 001 1048576
VCID: 295FC07F80BBFF69185-807C

2 Faults Found:
01207 - Control Module for Auxiliary Heater (J364) 
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 1
Reset counter: 149
Mileage: 83912 km
Time Indication: 0
Date: 2014.12.03
Time: 14:21:48

01320 - Control Module for Climatronic (J255) 
013 - Check DTC Memory - Intermittent
Freeze Frame:
Fault Status: 00101101
Fault Priority: 2
Fault Frequency: 1
Reset counter: 211
Mileage: 84662 km
Time Indication: 0
Date: 2014.12.23
Time: 09:32:22


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Address 18: Aux. Heat
Cannot be reached

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Address 19: CAN Gateway Labels: 6N0-909-901-7L.clb
Part No SW: 6N0 909 901 HW: 3D0 920 983 C
Component: J533 GW-K-CAN TP20 0616 
Coding: 7FF2FFAE3B011003
Shop #: WSC 26222 001 1048576
VCID: 70E9ED1B63E1CEA19FB-8025

1 Fault Found:
01207 - Control Module for Auxiliary Heater (J364) 
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 1
Reset counter: 149
Mileage: 83912 km
Time Indication: 0
Date: 2014.12.03
Time: 14:21:48


-------------------------------------------------------------------------------
Address 34: Level Control Labels: 3D0-907-553-V2.clb
Part No: 3D0 907 553 C
Component: LUFTFDR.-CDC- 3C3V0 1122 
Coding: 0005521
Shop #: WSC 01065 000 00000
VCID: 275BC64792AFC9190E1-8072

No fault code found.

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Address 36: Seat Mem. Drvr Labels: 3D0-959-760.lbl
Part No: 3D0 959 760 CA
Component: Sitzmemory D1 F 1722 
Coding: 0000004
Shop #: WSC 01065 000 00000
VCID: 6FEBEE677ADFD159861-803A

No fault code found.

-------------------------------------------------------------------------------
Address 37: Navigation (J0506) Labels: None
Part No SW: 3D0 035 680 HW: 3D0 035 680 
Component: RNS-MID H10 0210 
Revision: AB001001 Serial number: VWZ6Z7J0299011
Coding: 020500000000002200
Shop #: WSC 01065 000 00000
VCID: 5DB7A4AF447353C924D-8008

1 Fault Found:
00483 - Control Module for Auxiliary Air Heater 
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 5
Fault Frequency: 1
Reset counter: 149
Mileage: 83912 km
Time Indication: 0
Date: 2014.12.03
Time: 14:21:45


-------------------------------------------------------------------------------
Address 38: Roof Electronics Labels: 3D0-907-135.lbl
Part No: 3D0 907 135 E
Component: Dachmodul 0802 
Coding: 0004159
Shop #: WSC 01065 000 00000
VCID: 2547CC4FE8A3DB093CD-8070

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 3D0-959-933.lbl
Part No: 3D0 959 933 M
Component: 4Z HSG 8132 
Coding: 0000040
Shop #: WSC 01065 000 00000
VCID: 3A7D0F33761D44F161F-4B18

Subsystem 1 - Part No: 3D2 959 701 J
Component: Tuersteuergeraet FS 0201

Subsystem 2 - Part No: 3D2 959 702 J
Component: Tuersteuergeraet BF 0201

Subsystem 3 - Part No: 3D0 959 703 H
Component: Tuersteuergeraet HL 0201

Subsystem 4 - Part No: 3D0 959 704 H
Component: Tuersteuergeraet HR 0201

Subsystem 5 - Part No: 3D0 909 610 E
Component: 3O HDSG 2530

Subsystem 6 - Part No: 7L0 907 719 A
Component: Neigungssensor 0020

1 Fault Found:
00931 - Locking Module for Central Locking; Rear Right (F223) 
008 - Implausible Signal

-------------------------------------------------------------------------------
Address 47: Sound System Labels: 7Lx-035-4xx-47.lbl
Part No SW: 3D0 035 466 B HW: 3D0 035 466 B
Component: R12___DSP 12 Kanal 0230 
Revision: DBH04001 Serial number: BP218794953289
Shop #: WSC 00000 000 00000
VCID: 214FD85FF88B3729405-8074

No fault code found.

-------------------------------------------------------------------------------
Address 55: Headlight Range Labels: 7L6-907-357-A.lbl
Part No SW: 7L6 907 357 C HW: 7L6 907 357 C
Component: AFS-Steuergeraet 0136 
Revision: 00H04000 Serial number: 
Coding: 2214337
Shop #: WSC 01065 000 00000
VCID: 3B730A377E277DF97A9-806E

Subsystem 1 - Part No: 7L6 941 329 A
Component: AFS-Lst.-Modul l 0004 
Coding: 00000033

Subsystem 2 - Part No: 7L6 941 329 A
Component: AFS-Lst.-Modul r 0004 
Coding: 00000033

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio (J0506) Labels: None
Part No SW: 3D0 035 680 HW: 3D0 035 680 
Component: RNS-MID H10 0210 
Revision: AB001001 Serial number: VWZ6Z7J0299011
Coding: 020500000000002200
Shop #: WSC 01065 000 00000
VCID: 5DB7A4AF447353C924D-8008

1 Fault Found:
00483 - Control Module for Auxiliary Air Heater 
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 5
Fault Frequency: 1
Reset counter: 149
Mileage: 83912 km
Time Indication: 0
Date: 2014.12.03
Time: 14:21:45


-------------------------------------------------------------------------------
Address 65: Tire Pressure Labels: 7L6-907-273.lbl
Part No SW: 7L6 907 273 E HW: 7L6 907 273 E
Component: J0502 RDK 0006 
Revision: 00004006 Serial number: 00000700015249
Coding: 264900648C97BF000000000000
Shop #: WSC 01065 000 00000
VCID: 3A7D0F33711D44F161F-806F

No fault code found.

-------------------------------------------------------------------------------
Address 68: Wiper Electr. Labels: Redir Fail!
Part No: 3D2 955 120 B
Component: Front Wiper 3501 
Coding: 0013685
Shop #: WSC 01065 000 376832
VCID: 214FD85FFC8B3729405-8074

No fault code found.

-------------------------------------------------------------------------------
Address 71: Battery Charger Labels: 3D0-915-181.lbl
Part No: 3D0 915 181 D
Component: Batteriemanagement 2800 
Shop #: WSC 00000 000 00000
VCID: 2441D14BE39922012B3-8071

No fault code found.

-------------------------------------------------------------------------------
Address 76: Park Assist Labels: None
Part No: 3D0 919 283 E
Component: 10 Einparkhilfe 1107 
Shop #: WSC 00000 000 00000
VCID: 2C51396B8B49EA41E33-8079

No fault code found.

-------------------------------------------------------------------------------
Address 77: Telephone Labels: None
Part No SW: 3D0 035 385 B HW: 3D0 035 385 B
Component: J412 8609 
Revision: 00020000 Serial number: 0000B7A126108
Coding: 0020141
Shop #: WSC 01065 000 00000
VCID: 214FD85FF88B3729405-8074

No fault code found.


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## stefanuk (Jul 7, 2010)

Quick update to this problem.
I've checked my controller list via gateway and have controller 18 checked.
Controller J285 is registering as defective and looking at the controller list am i right in that this controls other controllers ie controller 18? if so, if i was to replace J285 would i get access to controller 18 back? Also it would appear that controller J285 is in the dash, is this correct. I'm hoping it isn't as i can see that it might be a dash out job to replace the controller!!!!


Stefan


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## n968412L (Apr 23, 2009)

Hi Stefan - I think you need to see what wisdom others come up with - but my instinct is that all the faults stem from a problem with Controller 18 - not least because we know it's very vulnerable to water ingress...

But let's see what other wise heads think......

Regards

Mike


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## stefanuk (Jul 7, 2010)

Hi Mike,

That would be my first thought but the heater was replaced just before christmas last year as there were fault codes related to the coolant sensor until it died completely.
I wasn't able to reach controller 18 prior to replacement and still not able to with a new heater.
I also get a noise that is difficult to describe that sounds like it coming from behind the instrument panel, the noise sounds electrical, a high pitched 'chatter'. I think this is where the J285 controller sits which i why i wonder if this could be the culprit. However i have noticed this noise start when the coolant temperature gets to around the 60 degree mark and continue. However if i do a longer journey, say around 25 miles the noise stops. This could be because the fan is not working so hard, or the temperature in the car has settled down........or i need a new battery!.

Regards,
Stefan


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## Gabs08PHTN (Jan 6, 2011)

stefanuk said:


> I've checked my controller list via gateway and have controller 18 checked.
> Controller J285 is registering as defective
> Stefan


Hi Stefan,
If you uncheck controller 18 at the gateway controller list, would it still appear as defective when you scan it?
Although it seems odd, controller 18 is not checked at my Phaeton's gateway controller list, eventhough it is there...
I would not think that your gateway controller, that is J285, is deffective as you would have many other comunication faults and the ones you have, are mainly related to the heater.
To me it is starting to look as a wiring or connector related issue. When you had the heater replaced did you have a chance to look at the condition of the connector? Also, if I am not wrong, the wire bundle than runs towards the heated is located behind the front left wing, have you had any repairs on that area?

Gabriel


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## stefanuk (Jul 7, 2010)

Hi Gabriel,

I'm afraid to say that things are getting worse. I now have no access to controller 8 as well controller 18!!
Also i've noticed that i can't increase heating, it seems to be at default 22 degrees now and will not go any higher. However it will decrease if i set the temperature lower, and will trigger the air con.
I think i'm now at the point it will have to go in to the dealer.


Regards,
Stefan


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## stefanuk (Jul 7, 2010)

Just to update on this problem. I ended up going to the dealer who fixed it in a couple of hours.
Re-coded the auxiliary heater so that it did not recognize it as a supplemental heater and now all working and the noise has disappeared.
I think the previous owner had coded it to work as a supplemental heater and when i checked that coding it was correct as i'd done it on my previous Phaeton.
So my question is, if coded in a GP 2 to work as a supplemental heater does it need a different code? if there is anyone with a GP 2 who has coded their auxiliary heater to work as a supplemental heater have you had any problems and did you use the coding that is well documented here?

Thanks,
Stefan


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## n968412L (Apr 23, 2009)

Hi Stefan - when you say it's now working OK... do you know it's working...? Or just not working at all?? 

All seems a bit odd cf my experiene on my GP0 and GP1...

Regards

Mike


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## stefanuk (Jul 7, 2010)

The auxiliary heater now works perfectly as an auxiliary heater, but the dealer disabled the supplemental heater coding as they say it was the coding that was causing the heater not to work and a by product has been that the constant buzzing noise i was hearing has also now disappeared so i can only assume that they were connected.
I coded the heater on my 06 Phaeton so that the heater was enabled and that worked fine.
So i wonder if the software is different between the GP0/1 and the GP 2 so that the coding to enable the heater to be suplemental is different.

I would be interested to hear from others with GP2's to see if they have they're heater coded for the supplemental heater and if they had the same problem i did.


Stefan


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## cbh123 (Aug 25, 2013)

What is supplemental heater? 
I have heard of auxiliary heat and residual heat, but not supplemental. Am I missing something ? 

Since the P is complicated, the solutions we find here need to be technically correct .. Otherwise they are kinda useless..


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## n968412L (Apr 23, 2009)

I think the terms supplemental and auxiliary are used interchangeably. I think the correct term is auxiliary. Not quite the same as a parking heater in concept... but the same in fact and implementation.


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## stefanuk (Jul 7, 2010)

I should aplogize, when i say supplemental heater i'm talking about the parking heater. I hope that clears up any confusion.

Stefan


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## perfrej (Dec 24, 2009)

A diesel Phaeton will have an supplemental, or augmentation, heater that helps the engine reach working temperature after a cold start. Without it you have to drive for a very long time before you get adequate heating for your cold butt. I think the newer diesels have electrical supplementary heaters, but up to 2010 or so it was the same physical unit as the parking heater.

When you paid for a parking heater you got a separation valve in the coolant circulation system and a different adaption in the heater controller.

Points cleared up!

/per


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