1998 gmc jimmy the ac and heater fan stops working and then starts working again I check all the fuses inside and under the hood could it be the relay under the hood help?

Answer sounds like a bad relay or dash switch Answer II My 1996 has the same problem. When the blower doesn't work, try this: Turn the fan to the highest setting, then with a screwdriver handle or rubber mallet, whack the top of the blower housing (upper left corner of the engine compartment. ) Not hard, just a good firm whack.

You should hear the blower motor sucking in air from the vent. If this works, the relay may not be the cause. It seems to be a weak connection.

I haven't opened the blower case yet to find out for sure. I just keep whacking it when I need it to work! Good luck.

- Mr. Dog when this happened to me it was the connector to the blower motor you might want to check there. The fuse and relay and resistor and dash swtch was good.