Operation

OPERATION

General
Feed from the positive battery terminal (C0192) is supplied to fusible link 3, fusible link 9 and fusible link 12 of the engine compartment fuse box (C0632) on an R wire. Fusible link 12 (C0570) provides a constant battery feed to the lighting switch (C0041) on a UN wire. A second constant battery feed is provided by fusible link 12 (C0575) to the lighting switch (C0041) on an RN wire.

Fusible link 9 (C0570) provides a constant battery feed to the headlamp main/dipped beam relay (C0587) on an N wire. The headlamp main/dipped beam relay is located in the passenger compartment fuse box.

Fusible link 3 (C0571) is connected to the ignition switch (C0028) by an N wire. When the ignition switch is turned to the 'ignition' position, current flows across the switch (C0028) to fuse 8 of the passenger compartment fuse box (C0588) on a G wire. Fuse 8 provides an ignition feed to the Central Control Unit (CCU) (C0593), which is mounted directly onto the rear of the passenger compartment fuse box.

Side Lamps
When the lighting switch is turned to the side lamp position, current flows across the switch (C0041) to fuse 16 and fuse 28 of the passenger compartment fuse box (C0587) on an R wire. Fuse 16 (C0582) provides a feed to the following on RO wires:
^ The RH side lamp (C0011).
^ The RH front side marker lamp (C0916) (NAS vehicles only).

Fuse 16 (C0583) also provides a feed to the following on RO wires:
^ The RH tail lamp (C0125).
^ The RH rear side marker lamp (C0918) (NAS vehicles only).
^ The rear number plate lamp (C0138).
^ The trailer pick-up (C0499).

All are earthed on B wires except the trailer pick-up, which is earthed on a W then B wire. Fuse 28 (C0581) provides a feed to the following on RB wires:
^ The LH side lamp (C0009).
^ The LH front side marker lamp (C0917) (NAS vehicles only).

Fuse 28 (C0583) also provides a feed to the following on RB wires:
^ The LH tail lamp (C0121).
^ The LH rear side marker lamp (C0919) (NAS vehicles only).
^ The trailer pick-up (C0499).

All are earthed on B wires except the trailer pick-up, which is earthed on a W then B wire.

Headlamps

Dipped Beam
When the lighting switch is turned to the headlamp position, current flows across the switch (C0041) to fuse 24 and fuse 25 of the passenger compartment fuse box (C0587) on a UO wire. Fuse 25 (C0582) provides a feed to the RH dipped beam bulb (C0011) on a UB wire. Fuse 24 (C0581) provides a feed to the LH dipped beam bulb (C0009) on a UK wire. Both are earthed on B wires.

Main Beam
When the lighting switch is turned to the headlamp position, and pulled back to the main beam position, current flows across the switch (C0041) to the main/dipped beam relay coil (C0587) on a UW wire. The main/dipped beam relay coil is located within the passenger compartment fuse box (C0587) and is earthed on a B wire.

The energized main/dipped beam relay allows a feed from fusible link 9 of the engine compartment fuse box (C0570) to provide a feed to fuse 18 and fuse 20 of the passenger compartment fuse box. Fuse 18 (C0584) provides a feed to the RH headlamp main beam bulb (C0011) on a UG wire. Fuse 18 (C0233) also provides a feed to the warning lamp located within the instrument pack (C0233) on a UG wire. Both are earthed on B wires.

Fuse 20 (C0587) provides a feed to the RH main beam bulb (C0009) on a US wire. The bulb (C0009) is earthed on a B wire.

Headlamp Flash
When the LH column switch is pulled back (but not past) spring pressure, the headlamps operate in exactly the same way as described in the Main Beam section until the switch is released.

CCU
When the lighting switch is turned to the main beam position, current flows across the switch (C0041) to the CCU (C0428) on an OU wire. The CCU also monitors the condition of the driver door switch, and the ignition switch. If the driver door switch is closed and the ignition switch in the 'off' position, the CCU will power its integral 2 kHz sounder.

For more information on the driver door switch, refer to the Anti-theft Alarm and Central Door Locking (CDL).

Headlamp Levelling
When the lighting switch is turned to the side or headlamp position, current flows across the switch (C0041) to fuse 28 of the passenger compartment fuse box (C0587) on an R wire. Fuse 28 (C0589) provides a feed to the headlamp levelling switch (C0093) on an RB wire. The switch (C0093) is earthed on a B wire.

The headlamp levelling switch has four pre-set positions. At each of the four switch positions, the contacts in the switch connect to a different resistance value to provide one of four different output voltages.

RH Motor
The headlamp levelling switch (C0093) is connected to the RH headlamp levelling motor (C0070) by a UB wire. By comparing the voltage provided by the switch against a feed provided by fuse 16 of the passenger compartment fuse box (C0582) on an RO wire, the motor moves the headlamp to the required position. The motor is earthed on a B wire.

LH Motor
The headlamp levelling switch (C0093) is connected to the LH headlamp levelling motor (C0071) by a UB wire. By comparing the voltage provided by the switch against a feed provided by fuse 28 of the passenger compartment fuse box (C0582) on an RB wire, the motor moves the headlamp to the required position. The motor (C0071) is earthed on a B wire.