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.

Tester[/b]

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.