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Discussion Starter · #1 ·
So this has happened a few times now, it's 30 degrees outside and my always perfect outside temp reading is at 97 degrees, and goes up to 107 degrees!
What happens is the air conditioning comes on in the car, or the vents open. One time I was able to turn the car off and back on and it reset to 30 some degrees.
Has this happened to anyone else? The exterior temp shouldn't adjust the interior temp...or maybe, I had the interior set to 76 degrees so the car must of thought it needed to cool the car.

Any thoughts?
 

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I'll say. either that ambient sensor is intermittently loosing its ability to read the temp correctly or maybe its laying up against the freon condenser. So, when the AC turns on, there are some pretty warm temps flowing thru it (condenser), and maybe the temp sensor is picking up on that.
The AC does in fact monitor the outside and inside temp sensors, and adjusts its temperature output into the cabin (as required) to best maintain the selected temp you have dialed in.
It says that at any time you desire, you can update that ambient temp sensor. That statement in the service manual says " The ambient air temperature value can be updated by an outside air instant update feature. To use this feature, press the following switches on the HVAC control module simultaneously" >>>> AUTO--A/C OFF--- REAR DEFOGGER. I've never tried it as of yet, but it would be interesting if it actually does work.
 

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Discussion Starter · #3 ·
Thanks for the help although it didn't seem to work. I did the reset with the car off in ACC mode, I did it in Park with the car running and even tried it while the car was driving. So there must be a problem with the sensor or the ground, I'll take a quick look at it and post up what I find.

Makes for an uncomfortable hour and a half commute because the HVAC system ignores your temp setting, or rather if you set the car to 71 degrees and it thinks it's 147 degrees outside, you get some nice cold AC, then when you turn off the AC you get a nice cold blast of vent air because it's truly 36 degrees outside. The only way to get heat in it is turn the temp to max then it cranks out the heat!

 

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Discussion Starter · #4 ·
Well I looked at the sensor and nothing seems amiss, so I disconnected it and pluged it back in. The temp reading was in the 140 degree range so I sprayed some cold water on it and it had no effect. I just unplugged it for now and will see how that works for my commute.
 

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Behind your right side headlight assy, is a 12 pin connector nearby. Labeled X106 (maybe). pin layout is A thru M. The ambient temp sensor wires from the HVAC go thru *it* on there way to the sensor. You can read its resistance using pins K an L,or see if any *minor* corrosion on the pins is evident, if you'd like.
 

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I had this problem in my old GTP and replaced the sensor and all was well. It was really cheap if I remember.
 

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Discussion Starter · #7 ·
Yea, I'll have to get mine replaced, maybe contact Greg at Pace.
 
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