# Outside temperature sensor



## TX170754 (Jun 5, 2010)

Hello everybody, 
As you may remember I was going to remove my front bumper in order to replace one of the headlight washer covers. Following Michael's instructions removing and reassembling the front bumper was not a monumental job, it went pretty well, removing and replacing both washer covers is another story. I've also retorqued the transmission pan bolts to 11Nm since I've had a small leak from the pan gasket, believe or not all the bolts were in need of retorque. Now I don't have any reading of the outside temperature on the cluster,could somedoby please indicate where is the outside temperature sensor located, I have the Bentley but I don't seem to find anyhting related to the sensor. 
Thanks, 
Dan


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## Jxander (Aug 5, 2008)

Dan: 

The outside or ambient temperature sensor is in the front bumper. Thus, i assume you forgot to reconnect the lead when reassembling the bumper. 

I even think Michael warns that it is easy to overlook that connection when reassembling. It seems his warning should be in boldface and a red font. At least your probably an expert on removal and replacement of the bumper. :banghead: 

The following is from the HVAC Self Study Guide for the Phaeton 


> The temperature sensor G17 is fitted in the
> bumper, whereas the temperature sensor G89 is
> located directly beside the air quality sensor in
> the plenum chamber.
> ...


 Hope that helps. 

Jim X


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## TX170754 (Jun 5, 2010)

I have checked last night, after eventually finding the sensor location, the sensor connector has not been disconected,since the bumper could be removed with it, I have "only"disconected and conected back the two main ones ( as indicated in Michael's procedure) on the driver side. Any idea what to do next ? I have also changed both air filters, not so sure where the other temperature sensor is. This is what I see in the cluster right now ----F


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## Buhts (Dec 24, 2010)

*Temperature readout*

The ambient temperature readout in my 2006 Phaeton V-8 is in Centigrade but the units read .....F. How can I change the units to actually read out in degrees F ?


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## PanEuropean (Nov 3, 2001)

TX170754 said:


> ...could somedoby please indicate where is the outside temperature sensor located...


Hi Dan:

Illustration is below. You probably just need to shove the connector into the back of the air temperature sensor more forcefully. There is a purple colour washer in there (kind of like what is on a garden hose) that seals up aginst the connector when you plug the connector in. It can require a surprising amount of force to get the connector to properly "click" into place, especially if the parts are cold.

Michael

*OAT Sensor Location*









*Same thing, in illustration format*









*What the individual components look like*


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## PanEuropean (Nov 3, 2001)

TX170754 said:


> ...not so sure where the other temperature sensor is.


There is another OAT sensor in the air intake plenum, on the driver side of the vehicle. It is attached to the left side wiper motor. But, that is used only by the HVAC system, it does not send a signal to the instrument cluster.

Michael

*OAT Sensor for HVAC system (not for instrument cluster)*


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## PanEuropean (Nov 3, 2001)

Buhts said:


> The ambient temperature readout in my 2006 Phaeton V-8 is in Centigrade but the units read .....F. How can I change the units to actually read out in degrees F ?


Hello, and welcome to the Phaeton forum.

The choice of units of display used for temperature, distance, and so forth is controlled using the big center display and control panel, in between the two front seats. I believe that you push the button (the hard-key) labelled SETTINGS, and from there, you can drill down into different menus that allow you to chose the units of measurement you want.

Being a new owner, these posts will be of great interest to you:

Store Settings for the Seat Memory buttons, key fobs, driver preferences (a complete how-to guide for setting up a new Phaeton)
....- A Useful Suggestion for Seat Memory Button Programming
Program the Homelink Garage Door Opener
....- Another Garage Door Opener Discussion
....- Yet another Garage Door Opener Discussion
Adjust the Clock, Keep the clock time synchronized with the GPS satellite constellation
....- additional information concerning GPS clock synchronization
Preset Sound System volume when car is powered up


Michael


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## Kenny G (Nov 8, 2010)

*OTS missing*

My car is missing the ots sensor is this something that can be bought on line or is it only available from a VW dealer.

Ken


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## PanEuropean (Nov 3, 2001)

It is a very common part, the same sensor is used for all VW products - Audi, Bentley, Bugatti, Seat, Skoda, Volkswagen, the works. Any VW dealer can order one for you, they are not expensive.

Michael


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## GeigerVW (Aug 15, 2012)

*A/C intermittent and outside air temperature readings keep going up*



PanEuropean said:


> There is another OAT sensor in the air intake plenum, on the driver side of the vehicle. It is attached to the left side wiper motor. But, that is used only by the HVAC system, it does not send a signal to the instrument cluster.
> 
> Michael
> 
> *OAT Sensor for HVAC system (not for instrument cluster)*


About two weeks ago I noticed that my A/C did not seem its normal meat locker cold self for a couple of minutes. But it was fine on the next drive and has actually been quite a bit colder than normal and I actually was wondering if the air sensor between the coin trays might be dirty.

On my commute home from work today, the A/C started but was not blowing cold and then the blower fan slowed back down and then after a few seconds tried to come up again. This cycling continued, even if I ran it up to full speed, it would come back down again. The water temp sensor is solid at 200F, but the outside air started at 90 degrees and kept climbing from there and did not go back down, even at freeway speeds, it fact it seemed to remain steadily high when idling at a stop light, but would immediately climb again once underway.

Since the A/C was blowing cold, if not extra cold, today, I am going to let everything settle and try it again later this evening. After reading the post above, I was convinced it is the QAT sensor, but if the sensors for the A/C and the cluster are not the same unit, I am not confident in my theory. Perhaps Michael could tell me what he would check first. I do not have my VAG-Com as I lended it to a friend of a friend who has moved with no forwarding address so I cannot pull those codes. Would a regular OBD scanner at the car parts place give the code?

My plan of action is:
1. Try again in 4 hours and see if the aux fans under the hood are spinning, then, if needed;
2. Pull the bumper OAT sensor and clean and reinstall, then, if needed;
3. Search for the second OAT in the intake plenum to see if I can clean that, then, if needed;
4. Take it to the dealer to have them diagnose.

Any insight/advice is appreciated.
G


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## Paximus (Aug 26, 2011)

I did have an air temperature sensor fail, the one near the HVAC air intake, so they are not bulletproof. They are not very expensive.

Chris


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## GeigerVW (Aug 15, 2012)

Paximus said:


> I did have an air temperature sensor fail, the one near the HVAC air intake, so they are not bulletproof. They are not very expensive.
> 
> Chris


Chris,

Thanks for replying. Two questions if you don't mind.

1. If the sensor you are speaking of failed, would I have seen both the symptoms of the A/C being wonky AND the dash temp gauge being off? I would think I would only have the A/C issue.
2. Where is the HVAC sensor at specifically? If you can provide a link to a picture showing it, I would appreciate it.

Boy I miss that VAG-Com. I knew I should have not loaned it out. 

G


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## GeigerVW (Aug 15, 2012)

*Update on A/C intermittent issue and outside air temperature readings keep going up*

The past two days, the outside temperature and humidity has been similar to what it was the day I had the issue. Both days there has been no issue so it may just be a ghost in the machine. I do plan to locate the two sensors and pull them and clean their contacts and reinstall just to reduce chances of this occurring again. 

Thank you again Chris for your reply earlier.

G


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## Paximus (Aug 26, 2011)

Hi,

The Outside Air Temperature sensor G17 (1J0 919 379A) at the front of the car is shown in post #5 in this thread (above). The HVAC air intake temperature sensor G89 (3D0 907 542) is fixed next to the Air Quality Sensor G238 (4B0 907 659B) under the plenum chamber cover.

As others have said in this thread, the HVAC uses the lower of these two sensor readings for comfort calculations, but I understand that the temperature display on the in-dash panel uses only the one at the front of the car.

Just for reference, the motorised temperature sensor G56 on the dash panel between the coin/ash trays is also busy looking at air temperature, as are the four other cabin footwell sensors. 

The ECU has its own air temperature sensors on the engine air intake(s), but these are not involved in comfort functions.

The Air Quality Sensor is a degrading part and will be trashed by excess chemical air pollution, silicone spray or old age.

I hope that helps.

Chris


*A is the Air Intake Temperature Sensor
B is the Air Quality Sensor* 









image (c) volkswagen


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## GeigerVW (Aug 15, 2012)

Paximus said:


> Hi,
> 
> The Outside Air Temperature sensor G17 (1J0 919 379A) at the front of the car is shown in post #5 in this thread (above). The HVAC air intake temperature sensor G89 (3D0 907 542) is fixed next to the Air Quality Sensor G238 (4B0 907 659B) under the plenum chamber cover.
> 
> ...


Chris,

Thanks for the diagrams and tips. Found them both, cleaned and so far all is good.

G


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