the fan switch has a tendency to be intermittent due to age and wear....
, however the fan is not completely controlled by the switch, there is some intelligence in the control head that looks at the temp being sensed by the in car temp sensor (behind the glove box under the dash, gets its input from air that is drawn in through the little grill next to the cig lighter).
The control head will not allow the fan to turn on if it senses an incorrect temp. but as air moves in the car, the fan will suddenly come on... alternative is to replace the whole ac control head as the switch itself is not supposed to be replaceable. OEM cost is around $380 new
sometimes you can squirt some electrical contact cleaner into it which might help.... but you need to take out the control unit and pop out the clear plastic front (very very carefully, break it and you get to buy a complete unit)
replaced mine, made a world of difference,
Doug '87 951
jereme wrote: