Where is the fuse for headlights a 1991 Chevrolet Blazer?

The fuse for the headlights on a 1991 Chevrolet Blazer is typically located in the underhood fuse block. However, there might be a second fuse or relay involved depending on the specific trim and options.

To be certain:

1. Consult your owner's manual: This is the most reliable source. It will have a fuse box diagram showing the location and function of each fuse.

2. Locate the underhood fuse block: It's usually a black plastic box located near the battery in the engine compartment. The cover should have a diagram printed on it.

3. Look for fuses labeled "Headlights," "Headlamp," or a similar designation. Sometimes it's a relay instead of a fuse, or there might be separate fuses for high beams and low beams.

If you can't find it in the underhood fuse block, there might be an additional fuse box inside the vehicle, often located under the dashboard. Check your owner's manual for its location and diagram.