LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2014 >> GLK350 Base >> Repair and Diagnosis >> Electrical >> Motors, Switches, Relays >> Electrical System - Body - 204 Chassis - 1 Of 6 >> Basic Knowledge >> Automatic interior lights control, function >> Automatic interior lights control, function - GF82.20-P-2200CE

Automatic interior lights control, function - GF82.20-P-2200CE

MODEL 204 except CODE (414) Power glass tilting/sliding roof as of model year 2009/YoM 08 

Fig 1: Automatic Interior Lights Control Block Diagram
G10084712Courtesy of MERCEDES-BENZ USA

Automatic interior lights control in general 

The automatic interior lights control implements the actuation of all components of the interior illumination as well as the warning and exit illumination.

The appropriate requests are generated automatically. The master control unit for the automatic interior lights control is the front SAM control unit.

The automatic interior lights control function encompasses the following subfunctions:

Additional function requirements for locator lighting 

Locator lighting function sequence 

In order to control the locator lighting, the front SAM control unit reads in and evaluates in the following signals:

The overhead control panel electronics is supplied with power by the front SAM control unit.

The following locator lighting components are therefore actuated indirectly by the front SAM control unit:

Additionally, the front SAM control unit on vehicles with code (954) Avantgarde or code (955) Elegance or code (876) Interior lights package actuates the symbol illumination for the following components corresponding to the set brightness value:

If the function is requested by unlocking the central locking system, all the lamps are switched off after t = 40 s or immediately, if the vehicle is locked again within t = 3 s of unlocking it. If the function is requested by intentionally leaving the vehicle, all the lamps are switched off after t = 15 s.

The locator lighting can be switched on or off in the instrument cluster. The status of the locator lighting is sent by the instrument cluster over the interior CAN to the front SAM control unit.

Additional function requirements for warning and exit illumination 

Function sequence for warning and exit illumination 

In order to control the warning and exit illumination, the front SAM control unit reads in and evaluates the following signals:

The front SAM control unit transmits the request to switch on the warning and exit illumination as well as the interior illumination via the interior CAN to the following control units:

The following components of the warning and exit illumination are actuated directly according to the door status:

The following components of the interior illumination are actuated indirectly through the power supply for the overhead control panel electronics over the front SAM control unit to match the status of the interior lamp automatic function switch:

Furthermore, the front SAM control unit actuates all footwell lamps at a brightness value of 100 %.

When all vehicle doors have been closed again and the electronic ignition lock control unit sends the circuit 15 ON status over the interior CAN, the interior lights are switched off.

The footwell lamps are then actuated again at the set brightness value for the symbol illumination.

IMPORTANT To preserve the on-board electrical system battery (G1), with circuit 15 Off all the activated lamps are switched off after t = 5 min. when a vehicle door is open and t = 8 s after the closing of the last vehicle door.

Additional function requirements for load compartment illumination 

Function sequence for load compartment illumination 

In order to control the load compartment illumination, the front SAM control unit reads in and evaluates in the following signal:

The front SAM control unit transmits the request to switch on the load compartment illumination via the interior CAN to the rear SAM control unit, which then actuates the following load compartment illumination components:

IMPORTANT To preserve the on-board electrical system battery, the ambient lamps and the trunk lamps are switched off t = 10 min. after the trunk lid or liftgate has been opened.

The rear SAM control unit reads in the status of the front doors from the front door control units and the status of circuit 15 from the electronic ignition lock control unit over the interior CAN, so that after the end of a journey and with open trunk lid or open liftgate the cargo area illumination can be activated again.

The ambient lamps and the trunk lamps are switched off after the trunk lid or the liftgate is closed.

Additional function requirements for interior illumination with ATA [EDW] alarm 

Function sequence for interior illumination with ATA [EDW] alarm 

The rear SAM control unit transmits the "ATA [EDW] alarm triggered" signal via interior CAN to the front SAM control unit.

The following components of the interior illumination are actuated indirectly by the front SAM control unit through the power supply for the overhead control panel electronics:

Furthermore, the front SAM control unit actuates all footwell lamps.

Additional function requirements for interior illumination following an accident with airbag deployment 

Function sequence for interior illumination following an accident with airbag deployment 

The interior illumination is actuated in order to provide better orientation for the occupants and the first air personnel following an accident.

The supplemental restraint system control unit sends the "Crash event" data over the chassis CAN to the front SAM control unit. The overhead control panel electronics are supplied with power via the front SAM control unit. The components for the interior illumination listed below are therefore actuated indirectly by the front SAM control unit:

Furthermore, the front SAM control unit actuates all footwell lamps.

IMPORTANT The interior illumination function following an accident with airbag deployment is deactivated under the following conditions:

REFER TO SYSTEM WIRING DIAGRAMS Automatic interior lights control electrical function schematic   PE82.20-P-2052-97FAA
  Overview of interior illumination (IBL) system components   GF82.20-P-9997CE