Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Question about 05 Sierra Coolant Temp Sensor

Just recently purchased an 05 Sierra for next to nothing. I noticed the coolant temp sensor works intermittently. One of the times that the coolant temp sensor wasn’t working I plugged in my obd2 and went to look at the raw temp data. I noticed that while the coolant temp gauge said that the temp was at zero, the raw data was at the normal ~200 degrees.

Does this mean that there may not be something wrong with the sensor itself, but maybe the cluster or something in between the two? I additionally got other codes for a random misfire, knock sensors, and both fuel trims running rich, which I believe are all from the computer thinking the engine runs cold at all times. Another concern I have though is overheating. If the e fans only run when the engine gets warmed up, would they not run because the computer thinks it’s cold?

Thanks for the help

If you see normal engine temp on the scanner, but the gauge shows zero, it’s the gauge.


1 Like

Does GMC use 1 sensor/sender for everything,
Or do they use a Sensor for the engine computer and a Sender for the gauge ?

I am not sure if there are stepper motors in your cluster, but if you are handy it can be a cheap fix.

So do you think it’s just a weird coincidence that I have a code for the temp sensor if it’s just the gauge that’s bad? The code doesn’t indicate that the sensor is malfunctioning, just something about the circuit is out of range. Thanks again

Why didn’t you mention the code at first?


As far as I know it’s only one sensor. I do get a code for the circuit being out of range, but no code for the sensor malfunctioning.

You’re right. I apologize. I thought I mentioned that when I said I had codes for everything else. That’s why I said “additionally”. I guess I missed that.

That being said, I’m going to replace the sensor anyway and see if it makes a difference. I got a new acdelco one for ~$12 online so I’ll see if that makes a difference

From what I’m seeing the 5.3L V8 uses separate temperature sensors for the coolant temperature, one of the gauge, and one for the computer.

1 Like