2004 Chevy Impala Heater Fan

Just today I got in my car and went to turn on the heater and it’s not working! I tried adjusting the fan speed and it made no difference. With the fan speed all the way on high I then tried adjusting position (floor, dash, or defrost). When I would change from one to the next, it sounds like a motor comes on for about 3-5 seconds and blows a little bit of air and then shuts off completely. each time that I would switch from one to another it would turn on and then off again. What could be the problem?

You have two choices. Either the HVAC control module is defective, or the blower motor control processor is defective.


Sounds like a heater door is stuck. Does the fan turn off or just the motor noise?

The fan comes on and blows very lightly and you can hear the motor trying to kick in but it shuts off after about 3 seconds.