With the exception of the brake light switch, all switches scanned by the light module are designed to switch to ground.
The following switches are scanned by the light module:
The light module receives further information via the I-bus.
When the light switch is in rest position, all contacts are closed (R < 1 Ohm) and the corresponding contact is opened (R> 1 MOhm) in the low beam or high beam position.
The lighting for the light switch is controlled separately by the light module. The lighting is illuminated at full intensity when the light switch is in the "OFF" position and the codable terminal condition is fulfilled. It is dimmed to the same level as the instrument and locator lights when they are switched on.
The brake light switch is permanently monitored by the light module when terminal R is activated.
It is designed as a Hall sensor and features 3 lines.
The test switch is not necessary.
The indicator lamp for the hazard warning function is located in the hazard warning button. It also serves as a locator light. When the hazard warning flasher is activated, the indicator lamp is switched to maximum brightness during the "ON phase" of the turn signal lamp and switched off during the "OFF phase".
The dimmed instrument, locator and function lights (terminal 58g) is activated when the light switch is in the "parking light" or "low beam light" position.
This takes place irrespective of the terminal conditions.
The voltage generated at terminal 58g is pulse-width modulated and dependent on the position of the dimmer potentiometer.
The dimmer potentiometer is switched to ground.
The lamps of the vehicle lighting system are monitored both when switched on and off (cold and warm monitoring).
The result is sent to the check control module via the I-bus.
The lamps are activated by means of transistors. Due to the fact that they are now short-circuit-protected, the lamp fuses are no longer necessary.
The lamps can also be activated via the diagnosis function.
The country-dependent functions of the lamp circuits are coded in the light module.
If one of the turn signal indicator lamps, rather than one of the auxiliary indicator lamps, is defective the flash rate will be doubled.
The auxiliary indicator lamps are activated at the same time as the front turn signal indicator lamps.
The light module controls the voltage supply for both automatic and manual headlight vertical aim control.
The voltage is switched at terminal 15 or "light ON". The headlight vertical aim control starts a reference pass when the supply voltage is switched on.