heat working on and off

[thetruckguy]

I have a 99 silverado and my heat works and then it doesn't so I tap on the heater controls for a while and it starts working can any one help me?

[ifixedit]

So are you saying it blows warm air and then it all of a sudden blows cold air? Or is it a case of the fan runs and then it quits and if you tap on the controls it runs again? I have a 98 Yukon, probably the same exact fan switch as you have. Mine was doing the same a few winters ago, the fan would run and then quit, I'd tap or wiggle the fan switch and it would start working again, sometimes would only work on high etc. If you have the same issue (and the switch has never been replaced) the fan switch is shot and just needs to be replaced, they are kind of cheesy cheap plastic construction and are fairly notorious for quitting all of a sudden. Local parts store like NAPA should have the switch. You might want to look into replacing the resistor while you're at it, good to do both at the same time.

 

If you have possible issues with your vehicle, this cold weather will sure bring it out in a hurry!