Heater/ AC Fan Motor running when off.

[mich77442]

Folk's I just replaced my dash and my fan motor is running when the heater/ac if in the off position. It is a a very low speed, but it is still running. Is that common, I did not realize it before I switched dashes. If not then maybe someone can tell me what I did wrong.

Thanks
Denny

[damaged442]

I think both of mine run slowly when the switch is off. My fan on my 77 doesn't run when the switch is on high though. I think the relay might be bad. :confused: I don't think it's possible to have one of our cars without having some sort of electrical gremlins. I think it's a law or something. Builds character.:D

[zodiacblue442]

Folk's I just replaced my dash and my fan motor is running when the heater/ac if in the off position. It is a a very low speed, but it is still running. Is that common, I did not realize it before I switched dashes. If not then maybe someone can tell me what I did wrong.

Thanks
Denny

Your fan motor is working correctly... it's part of the GM "astro-ventilation" system (that's what they called it) to circulate fresh air even when the heater/ac switch is in the off position. I've got a `74 Supreme and a `73 442 and both cars' fan motors operate as you describe.
Hope this helps.
Gary

[sledhead2]

Damaged442 says
My fan on my 77 doesn't run when the switch is on high though. I think the relay might be bad.


Check your high speed fuse. It is under the hood right about dead center on fire wall look for a thick orange wire there should be a fuse holder. Many times these holders burn up.:(

[keith455]

My fuse holder and fuse for the high fan is melted any idea what causes them to melt? I think it's the 2nd time it melted.

[PSU442]

when in the off position my fan is on low... when on low the fan is off. I make do...

[ragz442]

Both my cars [that are drivable] are no air cars and the blowers run at a very slow rate when off, I unplug my blower motors during the hot summer months.

[PSU442]

i wonder if there's something wrong with my low position.... huh. Do you have any problems when it rains during those months, Ragz? My Olds fogs up like a witch when it rains... it takes the defogger a century to do the job but it gets it done, eventually.