Individual headlights or taillights do not light up
Lamp filament burnt out - Replace lamps.
Fuse blown - Replace the appropriate fuse.
Oxidation of switch or relay contacts, lamp sockets or bases - Clean contacts.
Damaged wires, oxidation of their lugs or loose wire connections - Replace damaged wires, strip the lugs.
The direction indicator lamp flashes at a double frequency
One of the turn signal bulbs is burned out - Replace the bulb.
Direction indicators do not turn off automatically after completing a turn
Switch lever return mechanism stuck, turn signal switch drive ring lugs worn or broken - Replace three-lever switch.
Three-lever switch levers do not lock or switch
Lever detent balls jumping out or seizing, detent seats destroyed - Replace three-lever switch.