Cavalier fan will not run...
June 16th, 2013, 10:04 PM
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Cavalier fan will not run...
Hey, I know you probably get this a lot but I cannot find a fix here.
I have a 2000 Cavalier, 2.2L engine, A/C.
The radiator has been replaced, as has the ECT. I run the engine, it warms up and then overheats because the fan does not kick in around 195 F like it used to.
The fan works (tested it), the relay is good and plugged in correctly. However, with the engine running, I disconnected the ECT and the fan did NOT start up.
Not sure where to take this. Any help out there? Maybe a bad computer? The engine check light comes on after a while - is it possible I got a bum or wrong replacement ECT? I get 668 ohms resistance from it at roughly 147 F (according to the gage on the dash, anyway).
Anything would be a help. On the highway it's not an issue, but downtown, wheweee!
Steve
I have a 2000 Cavalier, 2.2L engine, A/C.
The radiator has been replaced, as has the ECT. I run the engine, it warms up and then overheats because the fan does not kick in around 195 F like it used to.
The fan works (tested it), the relay is good and plugged in correctly. However, with the engine running, I disconnected the ECT and the fan did NOT start up.
Not sure where to take this. Any help out there? Maybe a bad computer? The engine check light comes on after a while - is it possible I got a bum or wrong replacement ECT? I get 668 ohms resistance from it at roughly 147 F (according to the gage on the dash, anyway).
Anything would be a help. On the highway it's not an issue, but downtown, wheweee!
Steve
June 18th, 2013, 1:03 AM
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Well, I have narrowed it down to either a loose/broken wire from the computer that energizes the fan relay, or a defect in the computer itself. I will have to use my VOM to check whether there's an energizing current to the relay's coil when I disconnect the ECT.
Meanwhile, I have jury-rigged a switch box to the dash of my Cavalier. It does the relay's job of turning the fan on when the temp gets up there. I just flip the switch when the temp hits 195, shut it off when I hit the open road.
Any thoughts, guys? I see a lot of people looking.
Steve
Meanwhile, I have jury-rigged a switch box to the dash of my Cavalier. It does the relay's job of turning the fan on when the temp gets up there. I just flip the switch when the temp hits 195, shut it off when I hit the open road.
Any thoughts, guys? I see a lot of people looking.
Steve
August 16th, 2013, 4:40 PM
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sounds good!!
I think you are in the right path.... I believe you either have a bad wire or just a bad driver in PCM. if you look in the diagram the PCM grounds the path for the control side on the relay so if you are not getting ground out of that cable wich I believe is dark green pin #54 in the connector 2 on the PCM, then the PCM is not grounding your relay = bad PCM
if I am correct you can get those from junk yard for about $100 and have them reflashed for about $200 depends on your source. before that I would make sure you have good cables on the sensor check for open or high resistance or even run new wires just do it right, and use good heat shrink tubbing to keep moisture and water out. good luck
if I am correct you can get those from junk yard for about $100 and have them reflashed for about $200 depends on your source. before that I would make sure you have good cables on the sensor check for open or high resistance or even run new wires just do it right, and use good heat shrink tubbing to keep moisture and water out. good luck
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