2000 Chevy Prizm has a heater fan that only works on high
This only started a few weeks ago. The heater works ok but the switch that determines the force of the heat blowing only works on high. I'm thinking it might be the resistor thats bad but how do I know it's not the blower motor or heater relay?
If it was the motor or relay, it wouldn't work at all. It may be different for the Prizm but the other GM models have two heater blower circuits. One for the lower speeds and one for the high speed. They generally do not have a relay. Check the fuse box for a blown fuse. If all the fuses are good, you probably need a replacement resistor.
I agree with tenspeed
Tenspeed is correct about the wiring. The lower speeds are fed through the ignition switch. My cousins boyfriend has an 01 grand prix that had a similar issue. The dealer wanted $400 for the replacement heater head unit. Every time it was set to 1-4 the auto daytime running lights would shut off. Everytime the seat heater was turned on the DRLs would again shut off. 5 was the highest setting and it worked fine. Traced the wires back to the ignition switch which was only putting out 3.5 volts. It was enough to activate the daytime running light relay but not the seat heater module or blowers lower speeds and the extra draw from it removed the required power to run the DRLs. Key on engine off check all the fuses under hood and in car for battery voltage with a DC volt meter. It's really easy to check and will give you a positive answer
It's a resistor, if it was the motor it would not run at all, the resistor is lien for lower levels. No resistor is needed for high level as the motor runs at full power
agreed on the resistor ..it controls the fan speeds 20 dollar part located right beside the blower motor
Its the resister pack located behind the glove box and it probably bad. There are two bolts at the bottom of the glove box down close to the floor. One is hidden behind the side panel that covers the ECU. Then open the glove box and remove the three screws at the top. The resistor pack is just left of the blower motor that is held in by two screws. Replaced one today on my dads 2001 Chevy Prism. I think it cost $37.00 PLUS TAX. jb
I am here looking for how to get at the fan itself. About 5 years ago a guy was working on my car and noticed my fan only was working on the 2 highest speeds. He pulled out a bunch of shredded paper and crap a mouse had packed in there!! Well it started again this past winter, and recently I lost the 2nd highest speed. If it is paper I don't want to start a fire. Could I?
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