Hi,

I have a 2003 Silverado 1500 with automatic climate control. Last weekend as I was driving I heard the fan kick into high. I didn't think much of it until I got home and realized the fan would not shut off. It just stayed on full blast. After some research it appeared that the problem was the blower motor resistor. I thought, ok no problem. Easy fix. Well I replaced the blower motor resistor and now the fan does not come on at all, so I am stumped. I have read some suggestions that it could be the control module, but they also mentioned that it only fails in temps around -23 degrees F. It was nowhere near that cold when this happened. Any suggestions would be greatly appreciated!

 

check the wiring connector. I have an 06 that had same issue. It turned out, the connector was burnt on two pins. Also, check the amps on the blower motor, if it reads high, that could be causing failures in the connector and resistor. You will have to get the amp numbers for your motor to be sure.