Mercedes Benz C-Class (W204) 2007 - 2014 Training Manual: Restraint Systems / Crash-Active Emergency Lighting

Crash-active emergency lighting

In the event of a crash in which at least one pyrotechnical restraint system is deployed, sections of the interior illumination will be switched on:

• Front and rear interior lights (after a delay of 11 s)
• Front and rear door handle recess lights (after a delay of 11 s)
• Footwell lamps

Triggering of emergency lighting: Front fuse and actuation module (SAM-F) by a signal to the overhead control panel (OCP [DBE]) and the door control units (DCUs [TSGs]).

Activation by: Either by the airbag control unit via chassis CAN, or by the integrated crash sensor in the front SAM, if the CAN connection to the airbag control unit has failed.

Function of front SAM Delayed triggering of the interior illumination functions on receiving the crash signal or the alternative crash signal (whichever is received first) by the ARAMIS control unit or by the crash sensor in front SAM.

Time delay The preconditions are a time delay after the crash of 11 s AND "vehicle stationary". (Reason: Avoids dazzling if vehicle is still moving, does not affect door emergency unlocking (delayed by 10 seconds).

Output signals

After the time delay has elapsed (interior light module in front SAM), the front SAM transmits the signal to the OCP [DBE] to activate the front and rear interior illumination and to the door control units (DCUs [TSGs]) to activate the door handle recess illumination. In vehicles without door handle recess illumination, the transmission of this signal has no function. In vehicles with non-networked OCP [DBE] the interior lights remain off if the "door contact switch" is switched off (light switch in OCP [DBE]).

Deactivation of emergency lighting

• By operating the hazard warning flasher button
• By globally unlocking the vehicle using the ignition key
• With a circuit change from circuit 15R to circuit 15 (driving off again)

The interior lights can additionally be switched off manually and, if necessary, switched back on again via the door contact switch (light switch in OCP [DBE]).

Note

In vehicles with non-networked overhead control panel, the interior lights remain off if the interior light switch is manually set to "OFF". Consequently, if the emergency lighting is activated only the handle recess lights and the footwell lights are actuated.