External links now open in a new browser tab - turn this off in your UCP - Read more here.

A/C Blower motor dead...

E28 technical advice asked and given! Troubleshooting, modifications and more.
Post Reply
bmwfan1957
Posts: 525
Joined: Feb 12, 2006 12:00 PM
Location: Meridian, ID

A/C Blower motor dead...

Post by bmwfan1957 »

the a/c blower in my car doesn't blow anymore... so i have to open my sunroof to get the air to flow through... is there a fuse i should check?? i looked at all of them and as far as i could tell they were all fine... am i going to need a new one? it doesn't do anything at all when i turn the knob... and it went from working perfectly fine to not at all... it seems like a fuse-type issue to me. what do you guys think?

thanks, Bryan
a
Posts: 12473
Joined: Feb 12, 2006 12:00 PM
Location: Marshfield ,MA

Post by a »

Does the heater blower work? If not, fuse 14 IIRC, look for dirty or loose fuse contacts and/or melted plastic around the contacts. Replace the fuse with a NEW one. Next, but less likely is the blue snow flake switch or the drop out relay. The Link in my signature is to the wiring diagrams.
RonW
Posts: 5321
Joined: Feb 12, 2006 12:00 PM
Location: Long Island, NY

Post by RonW »

If the fresh air blower works, then the fuse is not the problem.

If your car is a late '86, or an '87 or '88, it has a fresh air control flap controlled by a little electric motor, which you can hear.

With the A/C button out, push the middle slider all the way to the right, and you should hear the little motor whiz. Now push the A/C button. You should hear the little motor whiz again, as it closes the door.

If you don't hear the motor, the A/C switch is the problem, because it isn't supplying power to the controller.

If you do hear the motor, your problem is most likely the A/C motor, though it could be the fan switch.

With the car off, stick a pointy object into the A/C vents near the ashtray and turn the motor. Does it turn EASILY? If not, the bushings may be shot. I doubt this is your problem, because the motor usually gives you a long period of whining as a warning. But if this is the problem, a shot of spray lube in each bushing will keep it going awhile.
bmwfan1957
Posts: 525
Joined: Feb 12, 2006 12:00 PM
Location: Meridian, ID

Post by bmwfan1957 »

no the heater blower doesn't do anything... (they're the same one right??)

i need to try cleaning all the contacts in my fuse box... the fuse for my tach and gas etc... only works half the time... but the fuse is good....
bmwfan1957
Posts: 525
Joined: Feb 12, 2006 12:00 PM
Location: Meridian, ID

Post by bmwfan1957 »

RonW wrote:If the fresh air blower works, then the fuse is not the problem.

If your car is a late '86, or an '87 or '88, it has a fresh air control flap controlled by a little electric motor, which you can hear.

With the A/C button out, push the middle slider all the way to the right, and you should hear the little motor whiz. Now push the A/C button. You should hear the little motor whiz again, as it closes the door.

If you don't hear the motor, the A/C switch is the problem, because it isn't supplying power to the controller.

If you do hear the motor, your problem is most likely the A/C motor, though it could be the fan switch.

With the car off, stick a pointy object into the A/C vents near the ashtray and turn the motor. Does it turn EASILY? If not, the bushings may be shot. I doubt this is your problem, because the motor usually gives you a long period of whining as a warning. But if this is the problem, a shot of spray lube in each bushing will keep it going awhile.
no it doesn't turn on in any position... (a/c or fresh air) although i'm thinking i probably should lube the motor just to be sure... thanks for that bit of advice! and my car is an '86...
Steve Haygood
Posts: 1943
Joined: Feb 12, 2006 12:00 PM
Location: Thomaston Ga
Contact:

Post by Steve Haygood »

different blower motors, either the common fan switch or a fuse most likely
bmwfan1957
Posts: 525
Joined: Feb 12, 2006 12:00 PM
Location: Meridian, ID

Post by bmwfan1957 »

well that's a bit of good news... i guess i'll try to clean all the contacts tomorrow... should be fun. ha...
Post Reply