Cabin Fans not working
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Cabin Fans not working A few weeks ago i noticed my car was starting to overheat, i stopped and popped the hood, i saw that my fans werent on, i went and put the AC on and the temp came back down to normal and my fans started working, both of them.
I used the car like this for a few days, if i saw the temp needle start to creep up id turn the ac on and the fans would come on and the car would not over heat.
after a few days, the car started running hot, and turning the ac did nothing, the fans where dead, i let the car idle and the temp came down, i babied it back home and it did not overheat. i checked fuses and relays, all where good, i went ahead and changed the thermostat and the termoswitch, so now my fans come on by themselves ( like they should) when the car gets warm, but i cant make them come on with the AC or just by running the fans inside the car, anyone know what it might be? my blower motor works fine.
I used the car like this for a few days, if i saw the temp needle start to creep up id turn the ac on and the fans would come on and the car would not over heat.
after a few days, the car started running hot, and turning the ac did nothing, the fans where dead, i let the car idle and the temp came down, i babied it back home and it did not overheat. i checked fuses and relays, all where good, i went ahead and changed the thermostat and the termoswitch, so now my fans come on by themselves ( like they should) when the car gets warm, but i cant make them come on with the AC or just by running the fans inside the car, anyone know what it might be? my blower motor works fine.
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Re: Cabin Fans not working
1) State the year, make, model, trim, engine of the car in question.
1) Coolant level could have been too low causing it to run hot. (absolutely expected with a D17 engine with a blown head gasket, and fans don't necessarily have to run during this type of overheat due to sensor location)
Locate the 'overheating common causes' sticky thread and have a read.
1) If the engine is in an overheat event, the AC system can be disabled by the PCM to reduce engine load. (I can't tell if that's what actually happened though)
1) After you replaced the parts, the cooling system is now actually full and radiator fans will work normally......until the radiator gets low again. Was the original fan switch bad? Maybe. You could test it using an ohmmeter and boiling water if you wanted to find out.
1) If the AC system now has a problem such as low freon or some electrical problem and cannot engage, the fans may not be turned on by the PCM.
1) Coolant level could have been too low causing it to run hot. (absolutely expected with a D17 engine with a blown head gasket, and fans don't necessarily have to run during this type of overheat due to sensor location)
Locate the 'overheating common causes' sticky thread and have a read.
1) If the engine is in an overheat event, the AC system can be disabled by the PCM to reduce engine load. (I can't tell if that's what actually happened though)
1) After you replaced the parts, the cooling system is now actually full and radiator fans will work normally......until the radiator gets low again. Was the original fan switch bad? Maybe. You could test it using an ohmmeter and boiling water if you wanted to find out.
1) If the AC system now has a problem such as low freon or some electrical problem and cannot engage, the fans may not be turned on by the PCM.
