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Grand Am 2000 GT. Cooling fan do not turn on.

Hi Guys, I Have a Grand Am 2000 GT, the car have been running fine till last week when I had to replace the water pump. But now the fans do not turn on when the engine get hot, and it start to overheat unless I turn the AC on, then the fans turn on and everything back to normal. I check the cooling tempeture sensor readings, relays and fuses, everything looks ok. I even check the wiring of the sensor using a resistor varitor, and the gage work ok too. What else could be wrong ??? , Am I missing something ?

Best Regards

Reply to
brisendd
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The sending unit for the gauge is not the same one that sends signals to the ecu/pcm. Perhaps the sensor for the fans is unplugged?

Reply to
« Paul »

Hi, Thanks for you replay, I check the car for another sensor, but didn't find any other that the one that is mounted in the front engine at the driver side. Do you have any hint were it can be ?

Regards

Reply to
brisendd

On the older cars there are several sensors, on the newer there is only one. I can't say when the cut-off was but it's around 2000, and if that is the type, then the PCM tells the fans to come on based on temp. GW

Reply to
Geoff Welsh

Or the wire melted in two. I had that happen to me once.

Jay

website URL: members.aol.com/orphantrainlocos/index.html All the world's a stage - and everybody's a critic.

Reply to
JCunington

I guys, I finally have time to check the car again. GW: Yes, you are correct there is only one sensor for temperature. I check the sensor with a multi-meter and was working correctly, but I changed any way. It did'nt resolve the problem. So I unplug the sensor with the car in idle, and the fans turn on. I guess the only thing left is that the computer is not working correctly. Thanks for all your ideas !!

Reply to
brisendd

ummm, uh, my news server doesn't catalog that far back (November) so I can't really comment specifically. I CAN say that disconnecting the CTS should make the fan come on, which does prove that the fan works, and the relay works, and those wires are fine. Unless I missed something, then you are correct to think that somehow the computer has "forgot" that it should turn the fan on at about 225 degrees fahrenheit or any time the AC is on. GW

Reply to
Geoff Welsh

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