E46 Fanatics Forum banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Ride of the Month Challenge!
1 - 3 of 3 Posts

·
Registered
Joined
·
65 Posts
Discussion Starter · #1 ·
My outdoor temp usually reads about 15/20 degrees F low. On hot days it can get up to a 30 degree difference.

The thing is it still changes normally, it'll just say 24 degrees F when its around 40 degrees. Or 57 degrees when its 85 outside.

I checked the sensor when I washed my car today and it's still there, still plug it, no wires showing, so it seems intact.

Any ideas? Suggestions? I've googled and forum searched but i haven't found someone with the same problem. I just want to know if it'll affect the car, haven't noticed anything yet but I only driven it for 2 months. Not even sure if somethings been wrong since before i got it.
 

·
Registered
Joined
·
10,552 Posts
I'm not sure, but I believe the temp probe is a thermocouple. It is either a thermocouple or a thermistor, and I think it's a a thermocouple.

In any case, the probe can suffer any number of issues that will cause it to read wrong. Thermocouples are more prone to this error than a thermistor is, which just reinforces my belief.

You are describing a bad temp probe.
 

·
Registered
Joined
·
8,056 Posts
Only thing I can think of is the resistance is off... but that shouldn't be the case unless it's a poorly made aftermarket sensor. Or perhaps other BMW models have sensors that mount the same way, but with different probes inside. I think it's a NTC thermistor
 
1 - 3 of 3 Posts
Top