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**cooljess76** · 08-05-2011, 01:02 PM

I never sat down and actually studied the schematic. All credit should go to Russ(Noneone2) and Bazar01 for taking the time to figure this out. Hats off to you guys! Bazar01, the schematic really gives a good visual understanding of how the circuits function. I think the reason it's confusing to people is because if the fan only works in high speed mode, one would think the high speed relay is functioning properly and since it doesn't operate in normal speed mode, the normal speed relay must be the culprit when in fact it's exactly the opposite. Replace the HIGH speed relay and it should fix the problem and allow the fan to work in normal mode again. Of course this probably only covers MOST cases. There's still a very slim possibilty that a faulty temp switch, pressure switch, fuse or fan motor may be the culprit, but I think it's safe to say that if your fan comes on when you turn the A/C on, but doesn't kick on when the engine idles for extended periods, you should probably replace the high speed relay first.

08-05-2011, 01:02 PM	#5
cooljess76 NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 iTrader: (6) Photo Gallery	I never sat down and actually studied the schematic. All credit should go to Russ(Noneone2) and Bazar01 for taking the time to figure this out. Hats off to you guys! Bazar01, the schematic really gives a good visual understanding of how the circuits function. I think the reason it's confusing to people is because if the fan only works in high speed mode, one would think the high speed relay is functioning properly and since it doesn't operate in normal speed mode, the normal speed relay must be the culprit when in fact it's exactly the opposite. Replace the HIGH speed relay and it should fix the problem and allow the fan to work in normal mode again. Of course this probably only covers MOST cases. There's still a very slim possibilty that a faulty temp switch, pressure switch, fuse or fan motor may be the culprit, but I think it's safe to say that if your fan comes on when you turn the A/C on, but doesn't kick on when the engine idles for extended periods, you should probably replace the high speed relay first.