24th Aug 2002, 16:34
The blower motor speed is controlled by a resistor, located behind blower motor. The blower motor has to be removed first, the part number is gm 15304891.
5th Jul 2003, 12:04
I just had the same problem on my 1999 grand prix SE at 42000 miles. The real cause of the problem was the AC condensate drain was plugged causing the green coating on the PC board to peel. Access to the drain is difficult from below the car I got soaked when I removed the elbow. I found that removing the radiator overflow tank (2 easy nuts) allowed easy access to remove or replace the rubber elbow. I think that checking this drain should be a once a year routine maintenance. Thanks, Geoff.
19th Jun 2004, 09:33
I have a 99 Grand Prix SE. Blower motor only works on 1&5. Sounds like I need to replace the blower motor resistor. Can you tell me where it is located in the car. Is it right behind the glove box? Thanks email@example.com.
21st Jun 2004, 08:47
Look above the blower fan, you will see the blower fan wire connect directly to it.
19th Jul 2005, 22:31
I have a 2002 GT with the same problem. Seems like a trend for Grand Prix. I didn't have to take the blower motor off to remove the resister, but it might help as the 2 screws are very tricky to get at. I used a bendable screw driver to get at it. Same problem with the coating peeling and appearing to burn out the board. I would like to know more about the A/C drain and how to clean it out, if anyone knows. Also the passenger side temp gauge isn't working, it is stuck at the same temp not matter where the slider is put. Any suggestions? I have heard it might be a door off the blower that is stuck. But I don't know how to get at it, any thoughts? Thank you.