Where is the horn relay on a gmc 2500 hd 2001?

On a 2001 GMC 2500 HD, the horn relay is typically located in the underhood fuse box. To access it, open the hood and locate the fuse box on the driver's side near the battery. The horn relay is usually marked on the underside of the fuse box cover, making it easier to identify. If you're having difficulty, refer to the vehicle's owner manual for specific diagrams and locations.