Coolant Temperature Sensor Bad?

are you still under warranty?

its gotta be the coolent temp sensor, or maybe its grounding a wire inbetween.

I'd guess it is a bad sensor, or the sensor got unplugged somehow.
I don't know where it is.
Did you do any mods recently where you might have bumped it?

I replaced the radiator about 6 months ago. It's an intermittent problem. Sometimes it works and other times it does not. It might be under warranty since the car has 48K miles on the clock. The stealership takes forever to fix anything when I bring it it. A damn oil change takes an hour! Thanks for the quick replies.

42qn30 said:

I've been having this issue on a off for a while now and need it fixed for winter so I can get all the heat I want. The information center that display the coolant temperature sensor displays ---*F instead of example: 180*F. The fan also runs constantly even with the blower turned off. Is this a proplem with the coolant temp sensor or something else I'm missing? Also where is it located?

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Are you getting plenty heat from the heater/blower when engine is fully warmed? The display reading should not effect heat output. Such as ..if you totally disconnected the temp sensor, the coolant would still heat to thermostat limits as usual,, you just would not know the temperature degrees as you would have no display only.
So do you just have an indicator problem or a heating up/delivery problem?

423

Just an indicator problem. The fan runs constantly so it slows warm up time. The theromostat seems to be working just fine.

If nothing "obviously" wrong.... sensor should do it. If warranty, let dealer do it.

423

I have the same problem with my car, but my A/C stop working too when I got the reading of ---. It looks like it is an intermitant failure, sometimes it works fine, (A/C and temp display) and sometimes it doesn't.

Its either a faulty sensor or the circuit has an open intermittently like a pinched or cut through wire.

The sensor is a resistor sensitive to temperature, as the temp changes the resistance does as well. Find the connector, unplug it and jump the connections with a paper clip or jumper wires. A temp value should come up. It might read freezing cold like -40*C or really hot like 140*C, that just shows the circuit is fine and the problem is the sensor.

The cooling fan is constantly on and the a/c doesn't work cause its a fail-safe mode done by the pcm. It doesnt know the engine temp so it wont allow the a/c to come on which would create more of a load and more heat, and it runs the fans to be safe as to not overheat. Just features to protect the engine.

That's a great response 08G5GT2.4L. I still need to replace the damn thing. I defiantly want to try the bridging of the terminals to confirm the bad sensor.

I have the same problem with my G5 it's a 2009 Pontiac. So when that happens to me I disconnect the battery push on the brake pedal for 10 seconds and wait 5 minutes and connect the battery again and everything works fine once again. But every so often the temperature reads nothing just the blank lines and the fan kicks on constantly running the AC doesn't work and my car goes into fail safe mode. So is it the sensor?

Post #10 answers your question

earnestsandoval1975 said:

So is it the sensor?

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