: Intermittent Temp Gauge Issue

06-08-13, 05:21 PM
I've noticed over the last few weeks that my temp gauge will just randomly stop working, it just sits at cold the entire time. This last week it did it three times on the way to work, on the way home it worked just fine. The coolant level is normal, A/C/heat works fine, do I have a bad t-stat? Or is there a sensor on the fritz that could cause this behavior?

06-08-13, 05:47 PM
I know the Vs at least have any issue with bad T-stats causing the car to not heat up fast enough. That will cause the temp gauge to go to zero, but also trigger a message on the DIC.

I'm guessing you have a bad temp sensor.

06-08-13, 06:11 PM
I have seen no messages on the DIC, just a gauge stuck on cold :) Where is this temp sensor you speak of?

06-08-13, 06:47 PM
The coolant temp sensor, but sorry, someone else will have to chime in on the location. I've never had to change it on the STS.

06-10-13, 05:18 PM
I had intermittent low temperature and the stored code was for a bad thermostat. Sure enough, changed it, all good now.

06-10-13, 05:44 PM
OK, I will grab my scanner and scan again...I have a CEL for a bad cat presently but will check to see if I have another DTC present beyond that one. It worked fine on the way to work and during lunch today. I hate issues like this that come and go as they please.

Maybe I could try cleaning the contacts for the temp sensor? Just need to know where it lives under the hood...

06-10-13, 08:55 PM
I wouldn't waste your time with contacts. If it was an open circuit the PCM would detect it and set a code saying that is the issue. If you have your own scanner (ex: AutoEnginuity -- not just a code reader) you can read the temperature and see if that is really the issue or if it is just the IP. Otherwise you may just need to spend money at the dealer with their scanner when the problem is occuring to get a diagnosis.