[lyrad1000]

I have a 2004 330ci with 88k miles on it. Once in a while, usually once every few hours of driving, the temperature alarm goes off repeatedly with readouts of "+50.0", and then "-40.0" I'm pretty sure this is Celcius, although I swear I had the display set to F, since way back when the temp alarm worked correctly, I remember it would beep at 37F. Needless to say, this alarm is happening in very mild weather (60F, cloudy weather) and mild driving conditions.


I assume this is just a broken thermostat somewhere.
Is this a simple enough fix? Or should I just send it over to the dealership?

Thanks for any advice.

 

[Spannerhead]

The outside air temperature sensor for the OBC is located in the left side fender liner, right behind the bumper. Check to make sure it's intact and plugged in first.

It's not a common failure item. If the sensor is busted or the wiring is torn up, you can get one from a local you-pull-it yard for peanuts.

 

[Archbid]

Probably frayed wire or busted connector. Post above is spot on

 

[BaliDawg]

I used this sensor repair kit last time mine went AWOL.
https://www.amazon.com/dp/B007H8DIG6/