Temperature gauge reads and suddenly drops while driving

SHAGGY1208

MEMBER
2007 PONTIAC G6
102,000 MILES

Temp. Gauge reads and suddenly drops while driving. Pulled the code and got temp sensor out of range, but as soon as I clear the code the gauge works again, not for long though. The stabilitrak light on the dash comes on and the brake lights stay illuminated until I press the brake pedal, when I release the pedal the brake lights illuminate again. Please help

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

The temperature gauge issue is likely due to a bad temperature sensor.

The coolant temperature sensor is located at the back of the engine on the thermostat housing (see diagram).
The internal resistance of a temperature sensor changes with the coolant temperature. It reads high resistance when cool and gets lower as it gets warmer.
You can test to see if the sensor is functional by using a multimeter and checking the resistance.

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works
https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

I have attached the resistance value chart as well as replacement procedure below for your reference.

The Stabil track issue could be due to a sensor or a module. As this is a different issue, please open a new thread by going to this link:

https://www.2carpros.com/questions/new

Please let me know if you have any questions.
Thank you.

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