Pontiac Grand Am Blower Speeds Not Working

2001 Pontiac Grand Am. My daughter has this car at college in Warrensburg,Mo, about 45 miles from home. She called me and said her blower motor quit blowing in the middle of winter. I had her bring it home on Friday evening so I could check it out.

The fuse in the passenger compartment was OK. The 30 amp fuse in the engine compartment was blown. I put a new one in and when I turned on the blower motor it instantly blew again. I took out the blower relay and it has a corroded post so I replaced it and the fuse. The blower now works on high speed only. It has 5 speeds and only works on #5.

What else can I check short of replacing the blower motor? Is there a speed control switch that can be replaced?

pontiac grand am

ANSWER:

A common cause for only high speed is the blower resistor. (See Below) It is under the passenger side of the dash, in front of the blower motor, up against the firewall. The circuits burn, and only high works because high is on a different circuit, and does not go through the resistor.

If not the resistor, then will need to check for inputs to the resistor from the fan speed switch. On the connector of the resistor, 1 wire will always be hot, then an additional wire will go hot as you turn the fan speed switch. Speed 1 will make one wire hot, speed 2 will make a different wire hot, and so. Those can be checked with a test light at the resistor connector.

Blower motor resistor module causes fan speeds to not work.

Question:
2000 Pontiac Grand Am 3.4L. Checked and tested all relays and fuses. Question: the a/c compressor clutch will not engage so the a/c does nothing besides blow hot air. I am out of ideas minus replacing the compressor or clutch. Is there anything else I should check before changing out those parts?

Answer:
Be sure the freon charge is good. If you put gauges on it and it shows a pressure, that does not mean it is freon. It could just be hot air that replaced the freon that leaked out. Air in the system will build pressure in an engine compartment that is hot. May sound silly, but have seen many a good mechanic get fooled by gauges. You should make sure the a/c relay clicks when you turn on the a/c, or better yet, swap the relay with another of the same kind in the fuse box and know for sure it is ok.

If you have a scanner, you can check to see that the PCM is getting and sending a signal to turn on the compressor. Lastly, check for power and ground at the connector for the a/c compressor, with the a/c turned on. If you have both power and ground on the appropriate terminals, you know that you have a bad a/c compressor. If need be, the compressors aren't that bad to replace. If you can get the front end of the car up on jack stands it makes the job much easier.


Ask A Question For FREE. No Login Required.


Q and A Main


How Things Work


Electrical