My father-in-law has a 2004 Ford Expedition (gasoline) and when we were in it the other night, the dash lights suddenly went out. All gages and other internal/external lights work, radio and clock works. Checked fuses #35 and #41 labeled "instrument cluster" in manual and they are fine. Read somewhere that it could be the dimmer switch? He has a trailer brake control (not factory) that is in it but don't know if that could affect them. Any ideas? Should I check a different fuse? I appreciate any input.