Outside Temperature Sending Unit

[johnpbaird]

Where izzit,......?(If there is one)
My Outside Temperature reading/s are totally inaccurate.
Is there a sending Unit?

 

[ccclarke]

The ambient air temperature sensor is located on the lower RH side of the radiator support. It is held in place with a plastic push-in retainer. While the sensor may be bad, there's a connector there, so maybe it's disconnected or the contacts are dirty. You'll need to raise the front end to access it.

You can learn the general theory of operation here :
http://www.gmserviceinsights.com/wp-content/uploads/2013/04/Service-Insights-Q2-2013-TC-lo-res.pdf

There's also an article that explains the different LANs that our XLRs use.

CC

 

[Anthony Cundari]

Dash Reset

I had mine in for routine service 3 years ago and when I left on a 90 degree day, the external temp registered in the mid 70's and didn't change after several starts and stops. I brought it back and the tech did a reset which I believe he did through the touch screen and not the AC controls but I'm not sure at this point. He said that the AC used the external temp as an input to control the AC output temps which weren't getting cold that day.

 

[johnpbaird]

Question:

ccclarke;45716]The ambient air temperature sensor is located on the lower RH side of the radiator support. It is held in place with a plastic push-in retainer. While the sensor may be bad, there's a connector there, so maybe it's disconnected or the contacts are dirty. You'll need to raise the front end to access it.


Your Right or mine??

Is it the Passenger side or the Driver's side?

Thanks!

 

[ccclarke]

RH side of the car as in passenger side.

CC

 

[johnpbaird]

In conclusion,........

First of all, The, "Plastic push-in" retainer/s wasn't on mine.
There are two "Star" head screws that are screwed into metal clips on the plastic shroud.
Don't force it or you'll break the plastic radiator shroud, (like I did).
The electrical plug to disconnect, is NOT the one on the unit, but about 10" inches higher.
I don't think it's serviceable but what the heck,.....Maybe GM has one for cheap,.........HA!

 

[kmariebox]

Two years later...

Well, here I am adding to this thread just about two years later... I pretty much have the same problem and it's almost humorous, as I live in Phoenix and we are now approaching July – As we are now dealing with 110° to 113° temperatures, my XLR is telling me the outside temperature is either 97° or 107° ... One could only wish – ha ha Wondering if either of you two came to any resolution or wound up getting any more detailed info.? Nonetheless, thank you CC for the link... Any type of 'theory of operation' always peaks my interest & holds my attention-- and I know it will do just that due to my timing of the circumstances

 

[XLRJIM]

Outside temperature guage

Where izzit,......?(If there is one)
My Outside Temperature reading/s are totally inaccurate.
Is there a sending Unit?

Neither the gauge on my XLR or Escalade is very accurate until 20 minutes or so of driving. I am on my 4th Escalade and have never found one to be accurate until at least 20 minutes of driving. Same thing with XLR. When I first got it had it in the shop several time for inaccurate out side temp with no resolution except to drive it for a while. After over 10 years kinda used to it.

JIM

 

[XLRATING]

Well, here I am adding to this thread just about two years later... I pretty much have the same problem and it's almost humorous, as I live in Phoenix and we are now approaching July – As we are now dealing with 110° to 113° temperatures, my XLR is telling me the outside temperature is either 97° or 107° ... One could only wish – ha ha Wondering if either of you two came to any resolution or wound up getting any more detailed info.? Nonetheless, thank you CC for the link... Any type of 'theory of operation' always peaks my interest & holds my attention-- and I know it will do just that due to my timing of the circumstances

Never been to Arizona but not sure I'd feel too much difference between 97 degrees & 113 - at that point my display could just say "Too Damn Hot"!

 

[xlrlist01]

Neither the gauge on my XLR or Escalade is very accurate until 20 minutes or so of driving. I am on my 4th Escalade and have never found one to be accurate until at least 20 minutes of driving. Same thing with XLR. When I first got it had it in the shop several time for inaccurate out side temp with no resolution except to drive it for a while. After over 10 years kinda used to it.

JIM

There are a number of reasons for why this should be so. If you have direven recently, heat from the radiator will give a higher than correct reading. The software attempts to allow for this by limiting how quickly it reports the higher temperature. Then there are problems with the sensor picking up heat from the sun, again causing inaccurate temperature readings. It is only after driving a few miles at a reasonable speed that the sensor unit can get enough airflow to report a reasonably accurate air temperature.

 

[kmariebox]

Thanks XLRJIM & XLRLIST01- Makes sense... I have read also that the sensor could need a cleaning/dusting off. If true, that would make sense, as it's very dusty here in the desert. Trust me, I don't drive my XLR in these storms, but when we get our monsoon/dust storms, those traveling walls of dust can get quite big (they can be a mile or two wide) and at high wind speeds, even with my garage door closed, my garage can accumulate quite the amount of dust if going through my neighborhood.

XLRATING- ... and of course, it's a dry heat- Ha ha!

 

[xlrlist01]

Thanks XLRJIM & XLRLIST01- Makes sense... I have read also that the sensor could need a cleaning/dusting off. If true, that would make sense, as it's very dusty here in the desert. Trust me, I don't drive my XLR in these storms, but when we get our monsoon/dust storms, those traveling walls of dust can get quite big (they can be a mile or two wide) and at high wind speeds, even with my garage door closed, my garage can accumulate quite the amount of dust if going through my neighborhood.

XLRATING- ... and of course, it's a dry heat- Ha ha!

That would make sense too. The ambient air temperature sensor is fitted low down near the right hand side of the radiator. It is fastened by a single push-in retainer after raising your XLR, ie from underneath. You also need to disconnect the wiring first. It looks like it runs across the width of your XLR, with the wiring on the outboard side (right hand side) and the sensor poking through into the air stream heading inboard towards the right hand edge of the condenser and radiator.

HTHs

 

[jeff brown]

outside temp sensor

Mine reads 75 all the time winter or summer. Too bad its incorrect sounds like Hawaii.

Got any ideas?

 

[Fireduck69]

That's the temp it will show if the connector is disconnected at the sensor I know from experience.

 

[McQuick21]

Fireduck69

That's the temp it will show if the connector is disconnected at the sensor I know from experience.

Thank you.

After reading this and having the same problem I checked mine to find the connector disconnected from the outside temperature sending unit. I did not have to get under the car as I just removed the air filter housing and reached down to plug it in. Great info. You could say I am McHappy for this quick fix.