Hello, a while back I replaced the temperature sensor behind the radiator that tells the outside temperature readings which shows up on the overhead display above the mirror. This is on a 2000 MC LS. The original sensor was giving me readings that were off by about 30 degrees of the actual temperature outside. I did try to reset it by driving 50 miles an hour for 30 minutes which I read somewhere as a way to reset the new sensor, but that didn’t work, I tried more than once.
Any help would be appreciated! Thanks!

 

https://montecarloforum.com/forum/general-monte-carlo-talk-9/how-fix-outside-temperature-sensor-49781/


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should be infront of radiator not behind otherwise you'd be reading engine bay temps.

Will give you an idea what to look for and where.

 

Help! I have replaced the sensor in front of the Radiator, the wires look okay but I am still not getting a correct ambient temperature on my display. Other than having a bad sensor (new from auto parts store), what else could be the problem? All the other readings on the overhead display read properly except the ATemp. The display reads E. OC when I check the Temperature.

 

I had the same problem 2 years ago where the outside temp would randomly show low by 30-50 degrees and replacing the sensor resolved it with no reset required. Just to confirm, your display is showing degrees F? I'm not sure what you mean by "E. OC" but that could be set to Celcius, which reads 32+ lower. If showing oF, you may have hit the lottery and got a bad new sensor too.

 

My OD is showing a reading: E OC as I stated, it is not giving me a Fahrenheit reading.
Does that sound like a defective Sensor? It is a New Sensor, but is of course possible that I got a bad one......

 

Page 2-97 of the 2001 Owners Manual shows how to change settings on the DIC. Press the Reset and Mode buttons for 3 seconds until a chime is heard to change the display between metric and English. Maybe yours is stuck.