I need help, winter is coming here in alaska and my heater fan on my 88 chevy suburban only works occasionally. i checked the hot wire staight in to the back and it seems fine. can anyone think of why this might happen?
Id say the fan is bad, first guess. When it doesnt work, make sure all the controls are set properly and with them all in the position that air SHOULD be coming out of the vents, find the blower motor either under the hood or under the dash and give it a pretty good whack with a rubber mallet or small hammer, if it starts working when you whack it, motor needs replacing, assuming you checked for any loose or bad connections already.
Please check the wiring harness going to the fan switch. You may find the red terminal that supplies power to the fan switch is burned at the edge and you have an intermittant short. Take the switch out and jump from the red terminal to the other terminals on the feed plug to see if the fan comes on. If it does the problem is in your switch.