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Daylight driving lights

Daylight driving lights




Daylight driving lights (dipped beam) will be on when the light switch on the dashboard is in position 0 and the ignition is in position ON (+15 and +54). Parking lights, rear lights and number plate lighting will also be on. The power feed to the dipped-beam lamps is controlled by DICE.

In certain markets, dipped beam is used as daylight driving lights.

To enable DICE to determine what position (0-1-2) the light switch (10) is set to, the control module uses information from TWICE and its own pin connection.

TWICE, which operates the parking lights, puts information onto the bus (ON/OFF). The ON message corresponds to switch position 1. The OFF message corresponds to position 1 or 2.

DICE pin 39 is connected to light switch pin 10, which corresponds to position 0. DICE pin 15 is connected to light switch pin 11, which corresponds to position 2.

Voltage +54 is fed via fuse 35 to pin 6 on the light switch. From pin 10 on the dipswitch, power is passed on to pin 39 on DICE, so that the dip relay is grounded via pin 4 on DICE and the relay closes. Power is fed through the relay via the filament monitor and on to the dipped-beam lamps, which come on.

Filament monitor

The filament monitor is located in the engine bay (relay box). It detects any break in the circuit to the lamps by measuring the current in the circuit. In the event of an open circuit, the filament monitor pin 9 grounds pin 23 of the SID unit. SID displays the message “FRONT LIGHT FAILURE”.

Diagnosis

Diagnostic trouble code 1160 is generated in the event of an open circuit or a short circuit to ground or a short circuit to B+.

DTCs are not generated if the voltage is below 11 V or during diagnostic communication.