Question about 2002 GMC Envoy

3 Answers

Outside temperature reads 50 at all times

I have read that the HVAC programming needs to be updated, that the ambient air temperature sensor needs to be replaced and/or the sensor can be reset by simultaneously hitting the Mode, FT Defrost and rear defrost.

I purchased a GM part # 15047946, a sensor, but it does not look like the sensor behind the top of the grill which is where I was directed to replace the ambient air sensor. If it does need to be replaced could you confirm the part number and location?

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  • karen_keesli Jan 08, 2009

    Mine is stuck on 50 too....all summer. it works in the winter. go figure.

  • starbucks284 Feb 05, 2009

    My 02 Envoy did the same thing, it read 50 all the time except a couple weeks ago it read -30 thru -36 for about an hour then went back to reading 50. I just did the reset (mode,fwd defrost, rear defrost) and now it reads -39 all the time. I looked at the sensor and nothing appers to be wrong with it.

  • Valk1520 Feb 09, 2009

    where is the sensor located? Any diagrams? Thanks!!!

  • Ralphddd May 05, 2009

    Yes me too -- same problem on 2002 OldsBravada... Did the aforementioned reset routine (Mode, FrontDef, RearDef) and now have the -39 readout at all times...

    Trust someone has final solution and will post it here...

  • dwisaacs
    dwisaacs Sep 27, 2013

    Sensor was not reconnected after service. Reconnected sensor and reset furning the HVAC off then pressing FT Defrost, Rear Defrost and Mode simultanelously.

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If your outside temp is wrong on your 2002 Envoy here is how you fix it. part number 15047946 sensor. looks like the wrong part..it's not. take the brace part off of it by pressing the clips and slide out the part you need. Loosen the 4-5 bolts from the top of the grill..attached to brace right on top of the grill..just pull the grill out about 3 inches..put your hand thru..it's driver side to the middle. original is grey box with connector. pull it out, reattach connector to new part and push the new piece in the hole..get the piece from the dealer..25.00...put screws back in grill brace. reset the temp by pressing front defrost, rear defrost and mode all at once. took me 15 minutes..and I'm a 55 year old girl:) you can do it!

Posted on Jun 23, 2010

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  • katdnc Aug 10, 2011

    Glad I read this before doing anything. Seems easy to fix and mine isdoing the same thing...50 degrees all the time except the other day it went to 27 and the A/C quit working. Back to 50 degrees again. Will get and replace the sensor. Thanks!!!!

  • Frank Starkey
    Frank Starkey May 08, 2014

    thanks this is more than I had yo go on before, will try to reboot first, and if that doesn't work will replace sensor, at least now I know whereit is located, thanks from the SWAMPDRAGON

  • Lisa bond
    Lisa bond Aug 23, 2014

    My 2005 Envoy is doing the same, stuck at 50, but I did the reset and it went to -39..... Now only warm air comes our of the vents. How do I get it back to 50, at least the ac worked then....

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Simulatenously hitting the Mode, FT Defrost, and Rear Defrost solved the problem.

Posted on Dec 30, 2008

  • dwisaacs
    dwisaacs Sep 27, 2013

    External temperature sensor was not reconnected after clutch fan was replace. I reconnected sensor. Reset sensor -turn HVAC off and press FT defrost, Rear Defrost and mode at the same time.

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2003 kia sedona ambient temperature reset

Posted on Oct 28, 2009

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