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Headlamps

Headlamps


Principle of operation

When the headlamps are switched on, the parking lights, which also include the rear lights and number plate lighting, will also light up. The parking lights are dealt with in a separate section.

Main beam

Full beam can only be switched on when ignition switch 20 is in position X.

Current will then be supplied to pin X of lights switch 10. Dipswitch 215 is spring-loaded.

When the lights switch is in position 2, current goes to pin 40 of ICE control module 500 and when dipswitch 215 is pressed, pin 8 of the ICE control module will ground dipswitch relay 8A.

Current (+30 circuit) is supplied via lighting relay 8 and dipswitch relay 8A to the main beam filaments via filament monitor 228B and fuses 8 and 9 (main beam indicator lamp 47G in the main instrument display panel is also supplied with current via fuse 8).

When the main beams are switched on, current for the parking lights is taken from light switch position 2 via pin 58.

Headlamp flasher

Main beams can be switched on regardless of the positions of the ignition switch and lights switch. By keeping the dipswitch pressed, current is supplied directly to the main beam filaments via filament monitor 228B and fuses 8 and 9.

Dipped beam

When the lights switch is in position 2, current will be supplied to pin 40 of ICE control module 500 and pin 33 of the control module will ground lighting relay 8. Current is then supplied via the dipswitch relay to the filament monitor and then to fuses 6 and 7 and dipped beam filaments 12.

If a main or dipped beam filament should fail, the relay in the filament monitor will operate and terminal C2 will be grounded.

Since pin 4 of the SID unit is grounded, the SID unit lights up "DEFECTIVE LAMP" indicator lamp 521 (main instrument display panel 1) or the INFO DISPLAY lamp and a message is displayed at the same time on the SID unit (main instrument display panel 2).

Safety circuit

When lights switch 10 is in position 2, a +X voltage is applied to lighting relay 8 from pin 56 of the lights switch to terminal 87A of the relay and then to the dipped beam bulbs via dipswitch relay 8A and filament monitor 228B.

It is not possible to switch between main beam and dipped beam.

Indicator lamp, lights on, 47V

The main instrument display panel incorporates indicator lamp 47V which shows when the headlamps are switched on. The indicator lamp is supplied with current from pin 58 of lights switch 10 via fuse 30.