2004 Monte Carlo blower motor will not shut off when car is off, keys are out, and not running. It blows one speed when it is happening. The only way to stop it from blowing is to disconnect battery. Unless, you unplug the motor from under the dashboard. It is in the 90s now and I need my AC back. Anyone know what is wrong with the blower, and how to fix it? Is it easy to fix?
Until you figure out the issue, pulling a fuse or relay might be easier to disconnect the power to the blower motor…
Tester may be on to something…
does it happen all the time? or just sometimes?
Does this have an a/c blower motor relay? If so, pull it out and look at it to see if it is burnt or melted at all. I wouldn’t think it would have 12v battery power on it, but I’ve seen crazier things before.
you can also try swapping it with the horn relay or wiper relay and see if it helps.
Yeah, having power to the fan with the key out is odd. Could it be a bad ignition switch? But a bad relay would be easier to check.
As mentioned, there is a blower control module. I replaced mine when it did the same thing. $25 at the junkyard. Mine was around the right kick panel somewhere.
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I’m also guessing the control module is the problem. OP, suggest check the prior forum postings here for similar complaints on GM vehicles, link upper right this page. Worthwhile to do a basic check battery & charging system too. As for the cause, was this car ever jump-started or used to provide a jump start to another car?
I don’t know how you check it. Maybe just unplug it to see if the fan stops. Probably a YouTube but I had the factory manual. But they are called different things like hvac controller, etc.
It appears there’s a 30 amp blower motor fuse residing in an under-hood junction block. Hard to say what effect removing that fuse might have though, the circuit diagram doesn’t appear to show the complete circuitry, or what components are removable with little trouble, and which aren’t.
That’s just the main fuse. Mine was under the seat. Hot all the time. The programmer/module/hvac controller. Decides when to energize the fan.
When the blower is running with the car off, pull the 30 amp fuse in the junction block under the hood.
If the blower stops, the problem is with the blower motor control processor.
If the blower keeps running, the problem is with the HVAC control module.
Tester
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+1 for Tester and just a FYI he also added/posted a diagram in his 1st reply (#2 post) if nobody has scrolled back up and seen it yet…
Yeah I looked at the schematic but to me it looked like the first fuse was energized with the ignition on and the 30 amp hot always. My main fuse was under the seat but I can’t say which one it was and would hav3 to get the manual out again to check. But whatever works. One of those two anyway.
Wouldn’t it be the other way around? If removing the 10A DIC/RKE fuse stops the fan, then the problem is with the HVAC Control module. Otherwise it is with the blower motor control processor.