Replace a Fuse: 1991 GMC C3500 Sierra 7.4L V8 Extended Cab Pickup

If your convenience lights, turn signals, seat warmers, stereo, headlights or other electronic components suddenly stop working, chances are you have a fuse that has blown out. The video above shows how to check and change blown fuses in the engine bay of your 1991 GMC C3500 in addition to where the fuse box diagram is located. Fuses should always be the first thing you check if your C3500 is experiencing electrical difficulties because they are relatively easy and inexpensive to change yourself. The more electronics your C3500 has, the more fuses it has. Some GMCs have multiple fuse boxes in the engine bay, so be sure to find the fuse(s) in question. Some components may have multiple fuses, so make sure you check all of the fuses that are linked to the component that is no longer working properly.

If you need to replace a blown fuse in your C3500, make sure you replace it with one that has the same amperage as the blown fuse. If checking and replacing the fuse for the component in question doesn't work, we recommend seeking assistance from a trusted professional mechanic. They should be able to figure out if the component needs to be replaced or if there is a short or some other problem with your C3500.