defroster fan problem

I have a 92 olds custom cruiser wagon (which I love) but am having trouble with the heater fan - sometimes it works, sometimes it doesn't. Suspect there is a chafed or broken wire somewhere? but where? LOL Anyone have any advice? Thanx Rosie

Well open your hood, now look behind your power steering pump on the firewall you will see the housing cover for your fan, wires pluged in there if you have air cond the relays are behind your right/side [passenger] headlight on rad support crossbar or as I call tool rest:edit if your car is a 3.3 Liter with A/C[ check your emission label on your humps[strut towers] upper left corner of label it will give engine discription] then the relay closest to your fender is the one for your heater fan don't worry about the rest other functions but still relays[engine cooling fan,A/C compressor,fuel pump] that's the order from your fender the heater fan relay first then the others in brackets

Thanx, I will give it a try :D