My 98 suburban just started acting up. The temp here in Oregon just dropped into the thirties and the heater fan (up front only) won't come on. I tried pounding on the plenum box on the passenger side and sometimes it kicks on. Unfortunately I not in need of warmth only during those moments.

It seems to be a short on the fan switch at the plenum; but before I tear into this complex, I thought I would ask if anyone had any other thoughs n what the cause may be.

...hhhhurry thththough... it's getting bad out there