1999 BUICK REGAL LS DIAGRAM OF FUSE BOX UNDER THE HOOD My horn stopped working on my '99 Buick regal.I went to check the fuse but it's not on the fuse diagramh fuse is it? If the fuse is not in the under hood fuse block look on the passengers side instrument panel should see at the end of the i.p. when you open the passengers side front door this helps luck. Buick Regal (1997 - 1999) - fuse box diagram - Auto Genius Jan 15, 2017Buick Regal (1997 – 1999) – fuse box diagram. Year of production: 1997, 1998, 1999. Instrument Panel Fuse Block. Some fuses are located in a fuse block on the passenger’s side of the instrument panel.