my 2005 malibu electric fans will only work when the AC swict is in the on position...tempeture sensor was change.
IF both fans are operating when the A/C is activated, everything should be fine. Is the car overheating at all? If not, I think that the fans haven't kicked on because the operating temp hasn't been high enough for the PCM to tell the fans to start. I believe if you were to disconnect the wire from the ECT, it will activate the fans. If the fans activate when the ECT is unplugged, all should be well.
The fans will not work with out the A/C being activated and then the engine will overheat.
Will they activate if you unplug the wire from the Engine Coolant Temp sensor? I think that's a fail safe. I would check your fuses and test or replace the relays. When you say it's overheating, is it really getting up to the red, or do you shut it down at about the 3/4 mark? You may need to let it get a little higher just to see if the fans kick on.
They do run when I unplug the Engine Coolant sensor, the car ran till the red mark and the fans did not activate,
Try replacing the relays next.
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