The rear fog lamps only operate when the headlamps are illuminated and the ignition switch is in position "II". The non-latching switch is positioned in the centre of the dash panel. When the rear fog lamps are switched on, the instrument pack warning lamp also illuminates. The fog lamps are automatically switched off every time the ignition is turned off.
Operation
Feed from the positive battery terminal is connected to the engine compartment fuse box (C632-1) by a brown wire. Current flows through fusible link 1 and fusible link 2 of the engine compartment fuse box, which are connected in parallel.
Fusible link 1 of the engine compartment fuse box (C907-1) is connected to the lighting switch (C041-1) by a brown wire. With the lighting switch in either the side or main lamp position, current flows across the switch (C041-4) to the headlamp relay (C282-87) on a blue wire. As the relay is not energized, the relay switch is open, preventing current flow.
Fusible link 2 of the engine compartment fuse box (C907-2) is connected to the ignition switch (C026-1) by a brown wire. With the ignition switch in position "II" (C094-1), current flows to the headlamp relay coil (C282-85) on a white wire. The relay coil is earthed (C282-86) on a black wire.
With the relay coil energized, the relay switch closes, allowing current to flow from the headlamp relay (C282-30) to fuse 6 of the passenger compartment fuse box (C580-11). Fuse 6 of the passenger compartment fuse box (C580-12) is connected to the rear fog guard lamp ECU (C543-2) by a blue/purple wire.
The rear fog guard lamp ECU (C543-4) is connected to the rear fog guard lamp switch (C064-2) by a red/slate wire. When the switch is depressed momentarily, it provides an earth (C064-3) on a black wire. The fog guard lamp ECU is also earthed (C543-1) directly on a black wire. When the ECU senses the second earth via the switch, it provides a feed (C543-3) to the instrument pack warning lamp (C233-4), the RH rear fog guard lamp (C512-1), and the LH rear fog guard lamp (C515-1). All three are connected in parallel by red/yellow wires, and earthed on black wires.