Temperature gauge stopped working

KIMBER.CORVI

MEMBER
2007 CHEVROLET EQUINOX
3.4L
6 CYL
2WD
AUTOMATIC
155,000 MILES

I replaced the temperature sensor and disconnected the battery. Drove great for 3 days then temperature gauge stopped working again. Dash says engine hot/AC off. Then the fan kicks on, A/C doesn't work. If I unplug battery and reset it, it will run for a day or an hour, it is always different, but it also will start working randomly also when driving. Can it be a ground, a module or the instrument cluster? Need help! Did change the thermostat also. If the thermostat is stuck open could that cause the temperature gauge to stop working?

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

The thermostat sticking would not affect the gauge or temperature sensor, but we can't rule out just a faulty sensor even though it was new. I have had many new parts fail.

It is possible that this is a ground but the PCM grounds these sensors on the low ref wire and the MAP sensor is grounded through the same circuit. So, if you have no codes for the MAP sensor then that circuit and PCM are not the issue.

I would suggest removing the connector and check the resistance across the sensor.

Here is a guide that will help with this:

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

I attached the wiring diagram below but let me know what the resistance is on the sensor, and we can go from there.

Thanks

Images (Click to make bigger)