I have 2001 impala 3400sfi. when I shut it down the heater motor keeps running,and runs the battery down. the switch only works on high. I have to pull the fuse to make it stop. Is the switch bad or a bad relay or bad motor or could it be something else? anyone have any answers. I would appreciate it. thank you
Most common fix for this problem is blower motor resistor. Of course if the resistor is bad it’s probably due to a blower motor that’s drawing too many amps.
If its climate control, I believe there would also be a blower control module that would cause the blower to run whether the car is off or not. Only way to stop it is to pull the fuse. On my Olds its about a $300 part.
An alternative could be a $3.00 switch mounted conveniently for the driver.