Symbol and ambiance illumination, function - GF82.20-P-2100CA

MODEL 207.3/4 

Function requirements, general 

• No overvoltage or undervoltage

Symbol and ambiance illumination in general 

The symbol and ambiance illumination feature provides the brightness-adjustable illumination of all controls as well as the illumination of the vehicle interior.

Symbol and ambiance illumination encompasses the following subfunctions:

• Function sequence for search and symbol illumination 
• Function sequence for ambiance illumination 

Additional function requirements, search and symbol illumination 

• Standing light ON (circuit 58 ON)

Function sequence for search and symbol illumination 

In order to control the search and symbol illumination, the instrument cluster reads in the following signals and evaluates them:

• Status of standing lights actuation, by front SAM control unit via interior CAN
• Instrument illumination brightness control status (continuous adjustment of switch and controls and symbol illumination brightness)

If the ambient illumination function is activated via the instrument cluster, it automatically switches itself on when the vehicle is unlocked using central locking (CL [ZV]). This results in the status circuit 58 activated and thus in the switch and controls and symbol illumination being switched on. If the driver door is then opened, the ambient illumination goes off. The status of circuit 58 is not applicable, and therefore the instrument cluster deactivates the search and symbol illumination. The controls in the vehicle are illuminated again only after circuit 15R is then switched on.

The instrument cluster uses the incoming data to generate the circuit 58d signal and sends it to the following control units to actuate the switch and controls and symbol illumination:

• Radio (with CODE 523 (MB Audio 20 radio) or CODE 510 (Audio 20 with CD changer) or CODE 505 (Radio 20 NTG5 non-navigation-capable) or CODE 522 (Audio 20 radio)) or Radio with auto pilot system (with CODE 511 (Audio 50 APS with DVD changer) or CODE 525 (MB Audio 50 APS radio)) or COMAND controller unit (with CODE 512 (COMAND APS with DVD changer) or CODE 526 (COMAND with single DVD drive (without navigation)) or CODE 527 (COMAND APS with single DVD drive (with navigation)) or CODE 528 (COMAND incl. DVD changer) or CODE 531 (COMAND APS))
• Front SAM control unit
• Rear SAM control unit
• Rear control unit
• Automatic air conditioning control and operating unit
• Left front door control unit
• Right front door control unit

The symbol illumination for the trunk lid emergency opening switch (with CODE 494 (USA version)) is actuated by the rear SAM control unit irrespective of the circuit 58d signal.

The radio or the COMAND controller unit sends the signal for circuit 58d over the telematics CAN to the Audio/COMAND control panel.

The front SAM control unit actuates the following components:

• Actuation via the instrument panel LIN:
  • Upper control panel control unit
  • Exterior lights switch (model 207.3 up to 31.05.2010)
  • Instrument panel switch group (up to 31.05.2013)
  • Analog clock (as of 01.06.2013)
• Direct actuation:
  • Overhead control panel electronics
  • Ashtray illumination in front cigarette lighter with ashtray illumination (with CODE 301 (Ashtray package/smoker package))
  • Exterior lights switch (model 207.3 as of 01.06.2010, model 207.4)
  • Armrest storage compartment illumination (as of 01.06.2013)
• Actuation over the instrument panel circuit 58d connector sleeve (Z50/1):
  • Left center air outlet symbol illumination
  • Right center air outlet symbol illumination
  • Left front side air outlet symbol illumination
  • Right front side air outlet symbol illumination
  • Rear vent symbol illumination (with CODE 581 (Comfort automatic air conditioning))

The front SAM control unit also sends the circuit 58d signal over the chassis CAN (up to 31.05.2013) or chassis CAN 1 (as of 01.06.2013) to the following control units:

• CDI control unit (with diesel engine)
• ME-SFI [ME] control unit (with gasoline engine)
• Steering column module control unit

The CDI control unit or the ME-SFI [ME] control unit sends the circuit 58d signal via drive train CAN to the electronic selector lever module control unit (with transmission 722.6, 722.9 up to 31.05.2013).

The electronic selector lever module control unit (with transmission 722.6, 722.9 up to 31.05.2013) directly actuates the following components:

• Shift gate symbol illumination (with transmission 722.6, 722.9 up to 31.05.2013)
• Transmission mode button for automatic transmission (with transmission 722)

The steering column tube module control unit actuates the following components:

• Actuation via steering LIN:
  • Steering wheel electronics
    • Left multifunction steering wheel button group
    • Right multifunction steering wheel button group
    • DIRECT SELECT lever (with transmission 722.9 as of 01.06.2013, with transmission 725)

The rear control unit actuates the following components directly:

• Left rear power window switch
• Right rear power window switch
• Soft top control switch (model 207.4)

The automatic air conditioning control and operating unit actuates the switch and controls and symbol illumination of the integrated controls directly and the rear automatic air conditioning operating unit (with CODE 581 (Comfort automatic air conditioning)) via climate control LIN.

The left front door control unit actuates the following components:

• Actuation via left door LIN:
  • Driver-side power window and outside mirror adjustment switch group
  • Switch group, left front seat adjustment (with CODE 275 (Memory package (driver seat, steering column, mirror)))
• Direct actuation:
  • Left front door handle illumination
  • Trunk lid release button
  • Left front door central locking interior switch

The right front door control unit actuates the following components:

• Actuation via right door LIN:
  • Switch group, right front seat adjustment (with CODE 242 (Electrically adjustable front passenger seat with memory))
• Direct actuation:
  • Right front door handle illumination
  • Passenger-side power window switch
  • Right front door central locking interior switch

Additional function requirements for ambiance illumination 

• Standing light ON (circuit 58 ON)
• Circuit 15R ON (footwell illumination, ambient illumination)
• Rain/light sensor signals "Darkness detected"
• Ambiance illumination activated

Function sequence for ambiance illumination 

Ambiance illumination includes the illumination for the center console, the doors and the footwells.

The intensity of the ambiance illumination can be adjusted in five stages using the "Settings" menu in the instrument cluster.

The ambiance illumination is functionally an integral part of the search and symbol illumination.

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

• Status of rain/light sensor, read in over the wiper/inside rearview mirror LIN
• Status of circuit 15, sent by the electronic ignition lock control unit via interior CAN
• Status of ambiance illumination brightness, sent by the instrument cluster via the interior CAN

The front SAM control unit sends the request to switch on the ambiance illumination to the following control units via interior CAN:

• Left front door control unit
• Right front door control unit

The front SAM control unit actuates the ambient lamp in the inside rearview mirror.

The left front door control unit actuates the door handle illumination for the left front door.

The right front door control unit actuates the door handle illumination for the right front door.

Furthermore, the front SAM control unit actuates the footwell illumination components at a defined value:

• Right front footwell lamp
• Left front footwell lamp

When the vehicle is unlocked using the central locking system, the ambiance illumination components are actuated at a set brightness setting. Opening a vehicle door or manually switching on the interior illumination causes the ambiance illumination to be actuated at a brightness setting that corresponds to 100 %. After closing the vehicle door, the ambiance illumination components are actuated again at the previously set brightness setting.

If no other ambiance illumination function is active, the ambiance illumination is controlled on the basis of the circuit 58d signal.

	Electrical function schematic ambiance illumination		PE82.20-P-2053-97EAA
	Search and symbol illumination electrical function schematic		PE82.20-P-2054-97EAA
	Overview of interior illumination (IBL) system components		GF82.20-P-9997CA