Hazard Warning Lamps: Description and Operation

Turn signal lamps / Hazard warning signal flashers

Turn signal lamps / Hazard warning signal flashers




This function is controlled by the left control stalk. The steering wheel module (SWM) (3/130) sends signals to the central electronic module (CEM) (4/56) via LIN communication to activate the turn signals (10/13-14 and 10/47-54).
To activate the indicator for the turn signal lamp and to supply the turn signal lamp with voltage directly via one output, the central electronic module (CEM) transmits information to:
- driver information module (DIM) (5/1)
- driver door module (DDM) (3/126)
- passenger door module (PDM) (3/127)
- trailer module (TRM) (4/110).
If a trailer or similar is connected the symbol for a trailer in the driver information module (DIM) will be activated in time with the indicator light for the turn signal lamp.
The power supply is pulsed and the turn signal lamps are activated 90 times per minute.
The hazard warning flasher is activated by closing the switch (3/6) and transmitting a signal to the central electronic module (CEM) to start the function. The central electronic module (CEM) then sends a signal the same way as when activating the turn signal, but to both sides. The central electronic module (CEM) also sends a signal to the bulb in the switch to indicate that the hazard warning flashers are on.
In ignition position I or II, there is a clicking sound from the driver information module (DIM). If the ignition is switched off, there is no sound, but the hazard warning flashers continue to flash.
If a fault occurs with a lamp, the central electronic module (CEM) detects the reduction in power consumption and the frequency is doubled on the side where the fault occurred. The display in the driver information module (DIM) will occur at twice the frequency.