I have problem with the fan on an 02 Blazer. the ac works but the fan works occasionally. any ideas why this would happen? Thanks in advance.

 

I take it you mean the blower fan for the heat and ac. Well if it only works occasionally I would say you have a loose connection somewhere or a failing blower motor maybe. I would look at the wires or vac lines going to the controls for vents and fan. Not sure if 02 has vac controls or electric you will know when you pop that part out.