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Light Module



Light Module

Brief description of components

Light module

the light module controls and monitors the vehicle lights. Information is received and sent via the data bus K-CAN SYSTEM.

Emergency operation properties of the light module: The light module is supplied with terminal 30 twice.

If a terminal 30 fails, the following are activated:
- Front lighting: low beam and parking light (each on one side).
- Tail lighting: On one side, the outer sidelights/brake lights are activated. On the other side, the inner taillights are activated. The vehicle thus still has lights on both sides. Confusion with a one-track vehicle (motorcycle) is excluded.
- Brake light: One side of the brake lights is activated with normal power (ECE coding). This leads to "one-track" braking, as if for example one brake light had failed.

In the case of a failure of the processor, emergency operating mode is activated. Emergency operating mode involves hardware that is completely independent of the light module. Emergency operation properties with failure of the processor:
- Vehicle lighting: At terminal 15 On, the following are switched on: Front low beam and outer rear sidelight/ brake lights left and right. The outer sidelights/brake lights left and right are not, as would be normal, dimmed to 10% of their brightness, but operated with full power. This ensures the function of the vehicle lighting irrespective of the position of the light switch.
- Brake light: With terminal 15 On, the left and right brake lights are switched on when the brakelight switch is operated (via a hardwired, direct line from the brakelight switch to the lamp drivers).

Function defects with failure of the processor:
- No turn indicators and hazard warning lights, no high beam, no headlight flasher, no fog lights, no rear fog light, no third brake light
- No communication across the K-CAN SYSTEM.
- No communication with the trailer module