Despite the fact that the weather has been in the 70's here for the past few days the temp display on my dash shows -36 degrees F. Any thoughts on what could be causing this? I suppose I could take it into the dealership, but would rather avoid doing so if there is a simple solution.

 

Fcope, I have the same issue but when it's 70F it reads 100F.
It started the last time I brought it in for engine control module
issue. I think they did something. I thing mine is just a
positioning issue. Yours sounds like it is just bad...
Time to see the DC Stealer.

 

Mine is also inaccurate - It always reads 10-20 degrees higher than the actual temperature. But I agree, yours sounds bad.

 

Your temp sensor is either disconnected or not functioning... when it dies it reads -36 ... check the sensor to see if it has been damaged / disconnected... it's a little black plastic pointy nub that is attached behind the front bumper on the driver side just behind the plastic grate, inboard of your fog lamp... Wish I had a picture for you, but mine has long since been removed...

If it is damaged or dead, you can buy a new one and install yourself for a few bucks... http://www.chryslerpartsdirect.com

 

Thanks, very helpful information. I will do that.

 

FYI, these are normally resistance devices, so if the temperature is reading off, check for corrosion on the wiring harness connectors. Usually plugging/unplugging them a few times is enough to clean them off enough to make them read right again.

 

Good call!
A temperature sensor is referred to us EE types as an RTC sensor (reverse temperature co-efficient). That means that as their temperature goes up, their resistance goes down.

Error:
If the reading is low there is too much resistance, additional resistance in the circuit can be caused by corrosion in the sensor wiring (that would explain the -36 degree reading).

If the reading is high there is too little resistance, more likely a failure in the detection module, or a short circuit in the sensor wiring.

Don't overlook the entire circuit wiring, including the wiring inside the vehicle. The ambient temperature sensor is routed directly to the instrument cluster; connector 2 pins 5 & 6.

 

I guess I'm one of the fortunate ones whose temperature sensor is dead on every time I've checked its reading versus the official temperature at the nearby airport as listed on the Weather Channel.

Frankly, I never expected such accuracy.

 

Midnightman,

You're not the only one that feels that the temperature sensors in cars aren't accurate. Seems like everyone does!

I've been checking the sensor in my RAM and CF against every temperature display I see (like banks and so forth).

The sensor in my RAM is always within 1 degree, except when I first start out. I think that's because Dodge mounted it in the hood, just above the radiator, and it takes a little airflow to get it adjusted to the outside air.

The sensor in the CF is mounted, as pointed out above, in the lower grill work and it is always within 1 degree of the bank's temperature display. My carpool buddy did, on one occasion, prophet the theory that it was colder outside than my CF gage indicated (101), and that the reason for that was because the sensor is close to the road and includes heat coming off the road (we were moving at about 40 MPH at the time).
He might be right about that, I haven't taken any time to try to prove/disprove his theory.

 

Mine's dead on as well, and I use my home thermometer as my standard. It's in the shade. I never use a bank sign because as I drive down the main drag in town there are 4 banks and none of them ever have the same temp, winter or summer. And I've seen at least 8 degrees difference between them.

 

Mine is always 1 or 2 degrees higher than the temp that's posted on the signs. But I just figured it was because of the sensors location being so close to the highways surface, it was reading the heat that was "radiating" from the asphalt.