So where do I find the fuse box on a 1981 GMC Cabarillo, and if I replace the fuses will it allow the heater to work, if not should I then take it to and auto repair shop.

Hello howard. There is a fuse panel to the left of the steering column behind a removable panel. Begin by checking and changing the fuse to the heater. The other posssible problem is the heater relay which is a plug in located under the dash, to the right of the steering column. IF the relay is bad the fan will not come on. IF you check and/or change each of these items and your heater still doesn't work then you probably will have to go to a repair shop. Joe

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