Constant HVAC blower motor running

Lo all,
The other day my battery was dead, jumped it, ran fine. Next morning battery was dead again. Now, with a charged battery, I notice that the HVAC motor runs very softly when the car is OFF!! I tried shutting off the AC before I turned the vehicle off, but it still runs. The only way to shut if off is to disconnect the wiring harness at the passenger side access. Any suggestions would be greatly appreciated.

Could be a number of things, especially if you have the computer climate control or a newer 05-up. On the models w/manual systems, you're limited to a few basic things such as a bad switch, shorted control module, or sticking relays. The automatic systems have many more sensors involved that can contribute to your symptoms. Could also be a bad blower control module. What year is your vehicle and which HVAC options do you have (manual,auto, auto w/manual rear, auto w/auto rear controls, etc)?

clemclan said:

Lo all,
The other day my battery was dead, jumped it, ran fine. Next morning battery was dead again. Now, with a charged battery, I notice that the HVAC motor runs very softly when the car is OFF!! I tried shutting off the AC before I turned the vehicle off, but it still runs. The only way to shut if off is to disconnect the wiring harness at the passenger side access. Any suggestions would be greatly appreciated.

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did you ever find the source of your problem. I have the same problem. 2nd time. last time in 2003. gm replaced a whole bunch of stuff. any help would be appreciated.

more details on blower motor that won't stop

I have a 2001 Tahoe with climate control.

I have an 03 Yukon with climate control and I have had a similar problem. It is probably a short in the hvac module. Been trying to find the part number but no luck yet.

Fixed

I fixed the problem. Not sure of the cause. I disconnected the control module from the dash. when I plugged it back in, it worked. Maybe that reset something. All better now.