Low coolant light keeps coming on?

[Robin Whitworth Statzer]

Our 2001 Tahoe has a low coolant light that keeps coming on. We just had the head gaskets done, the radiator is only 2 years old (it's the 3rd one) and we just put in a new coolant reservoir. Any ideas why this keeps happening? We top off the reservoir and the light will stay off for a few weeks, but eventually comes back on. TIA!

[Coby7]

When you replaced the tank did you replace the sensor? The surface of the sensor might be contaminated from the head gasket incident make sure the pick-up surface is clean. May need to soak it in vinegar for 10 minutes.

[Robin Whitworth Statzer]

According to the hubby when we put in a new reservoir tank it came with a new sensor (he had to attached a couple wires)?

[Coby7]

Did he apply dielectric grease to the pins prior to installation?

[Colossus]

Ditto on the sensor. Have it tested. Even though it is newer, it can still have gone bad. Might need to hook up a GM Scan tool/Tech II to toggle the sensor or check the readings of that sensor via the Tech II, A good independent repair facility should have the tool. Probably save you some $$$ vs taking it to the stealership.

Edited January 7, 2017 by Colossus

[Robin Whitworth Statzer]

Thank you! He did not do the grease on the pins...that will be a next step...

[Swimmer8366]

Sounds like your losing coolant that it's not a sensor problem if your adding coolant to get it to go off check your water pump.

 

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[Swimmer8366]

Mine did this for months than the pump blew out completely put new pump in not a problem with coolant since.

 

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