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Parking lights

Parking lights

The parking lights are on whatever the position of the ignition switch when the light switch is in position 1. They also go on when the main lighting is on.


So that DICE can safely determine in which position (0-1-2) the switch (10) is, it uses information from TWICE and its own pin connection.

The parking lights are controlled by TWICE which gives information to the bus (ON/OFF). The message ON corresponds to switch position 1 and the message OFF corresponds to switch positions 1 or 2.

DICE pin 39 is connected to switch pin 5, which corresponds to position 0. DICE pin 15 is connected to switch pin 4, which corresponds to position 2.

The front parking lights are powered directly and the rear are powered via TWICE, which monitors the rear parking light bulbs.

Power to the switch (10) is supplied via fuses 29 and 30 to pins 23 and 46 respectively on TWICE.

The rear parking lights are supplied with current from pins 45 and 68 via resistors inside TWICE. The control module measures the voltage drop across the respective resistor and thus determine the current passing through TWICE to the respective parking light circuits. The left light circuit goes in on pin 23 and out on pin 45. The corresponding pins for the right light circuit are 46 and 68 respectively.

Filament monitor

The current to the respective pins passes through a shunt resistor in each circuit in TWICE. In the event of a filament failure, error information is sent to the bus. SID generates an acoustic alarm signal and displays REAR LIGHT FAILURE.