I have a 99 pontiac Grand prix. The AC and fan only work on fan speed 5 (max speed) and it takes time for it to come on then. I changed the fan motor resistor a few months ago after having about the same problem, but this time it's a little different acting. I checked the blower motor resistor and it's ok. Could you tell me what else it could be?
It could be the blower high speed relay. Current for the lower speeds passes through the normally closed contact on the relay. Swap it with an identical relay from elsewhere on the vehicle to find out if it's bad.
Where do I find the relays??
Sorry for the delay. Have been out of town for the past couple of days.
It looks to me from the schematic for your machine that the blower relay is integral with the resistor module. Did you notice it when you replaced the module last time?
If the relay is indeed relatively new then another possible cause for your woes comes to mind. The speed control switch on the dash might be to blame. Are you handy with a multimeter?
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