Hummer H3 (2007) - fuse box diagram - Auto Genius Nov 01, 2018Hummer H3 (2007) – fuse box diagram. Year of production: 2007. Engine Compartment Fuse Block. The engine compartment fuse block is located on the driver’s side of Hummer H3 Fuse Box Diagram » Fuse Diagram Look at the silver-colored band inside the fuse. If the band is broken or melted, replace the fuse. Be sure you replace a bad fuse with a new one of the identical size and rating. If you ever have a problem on the road and do not have a spare fuse, you can borrow one that has the same amperage.