No A/C or Heat or Fan air

I have a 93 GMC Sierra pickup 4.3 liter 6cyl 1500 long bed. Occasionally my fan would stop working and I’d have to reach down under the passenger side and give it a good whack and then it would start working again. Well about six months ago, it did it again but this time the “Whack” didn’t work so in my frustration, I whacked just above the controls on my dash and it all stopped working. No fan, no a/c, no heat, no display. I checked all the fuses and even removed the whole control module and checked for 12 volts at the plug. Thinking that I may have damaged the control module, I purchased a used one, and installed it to no avail. HELP!!!

Most likely a bad connection somewhere. Or the motor was just about to fail and it finally burned out.

It sounds like there is a bad power connection somewhere. Check your fuses also. If you can’t find the problem by moving wire connections around I suggest you get a service manual and trace the power to the panel using a test light probe to check for power.

[b]That’s the classic symtom of a worn out blower motor.

Replace the blower motor and the vent system will work again.


Thanks for the info but my display panel is totally black. No digital readout at all.

A bad motor can draw too much current for the controls and blow them out after an extended period. It can heat stuff up chronically without blowing the fuse.