Headlights Circuit Description (Domestic)

Voltage is available at all times to the headlamp switch from the LIGHTING fuse through CKT 42 (RED). The headlamp switch has the following positions:
- OFF
- Park lamps position
- Headlamps position

When the headlamp switch is in the headlamps position, voltage is provided to CKT 10 (YEL) to the headlamp dimmer switch. The headlamp dimmer switch is part of the multi-function switch on the steering column. The headlamp dimmer switch position is changed by pulling the switch lever along the axis of the steering column. The dimmer switch allows the following selections:
- High beam
- Low beam

When the low beams are selected, voltage is available on CKT 359 (PPL). The low beam current flows through the normally closed daytime running lamp relay, and continues on CKT 12 (TAN) to the headlamps. When the high beams are selected, voltage is available on CKT 11 .(LT GRN) to the headlamps. The left headlamp is grounded at G108, and the right headlamp is grounded at G109.

The headlamp switch has an integral 17 A circuit breaker. If the supply circuit to the headlamps is shorted to ground while the headlamps are on, the circuit will be heated by excess current. The heat causes the circuit breaker to open, and it resets when it cools. Because of the action of the circuit breaker, the headlamps will rapidly cycle on and off if they are operated while the supply circuit is shorted to ground.