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

MODEL 218 

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 (with CODE 877 (Ambiance illumination)) 

Additional function requirements, search and symbol illumination 

• Standing lights ON (circuit 58)

The status "Standing light ON" is sent by the exterior lights switch directly to the front SAM control unit.

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 causes "Standing lights actuation active" status to be set, which also activates the search and symbol illumination. If the driver door is then opened, the ambient illumination goes off. "Standing lights actuation active" status is canceled, and 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 transmits it to the actuation for the search and symbol illumination via the interior CAN to the following control units:

• Radio (up to 31.08.2014 with CODE 510 (Audio 20 with CD changer) or CODE 523 (MB Audio 20 radio), as of 01.09.2014 with CODE 505 (Radio 20 NTG5 non-navigation-capable) or CODE 522 (Audio 20 radio))
• Radio with auto pilot system (with CODE 525 (MB Audio 50 APS radio) or CODE 511 (Audio 50 APS with DVD changer))
• COMAND controller unit (up to 31.08.2014 with CODE 512 (COMAND APS with DVD changer), CODE 526 (COMAND with single DVD drive (without navigation)), CODE 527 (COMAND APS with single DVD drive (with navigation)) or CODE 528 (COMAND incl. DVD changer), as of 01.09.2014 with CODE 531 (COMAND APS))
• Front SAM control unit
• Automatic air conditioning control and operating unit
• Left front active multicontour seat control unit (with CODE 432 (Active multicontour seat))
• Right front active multicontour seat control unit (with CODE 432 (Active multicontour seat), without CODE 494 (USA version))
• Left front door control unit
• Right front door control unit
• Left rear door control unit
• Right rear door control unit
• Overhead control panel control unit (with CODE 414 (Power glass tilting/sliding roof))

The switch and controls and symbol illumination of the trunk lid emergency opening switch (S88/10) (with CODE (494) USA version) is actuated by the rear SAM control unit irrespective of the circuit 58d signal.

The radio, the radio with auto pilot system, or the COMAND controller unit sends the circuit 58d signal via the telematics CAN to the Audio/COMAND control panel and the Audio/COMAND display.

The front SAM control unit actuates the following components:

• Actuation via the instrument panel LIN:
  • Analog clock
  • Upper control panel control unit
  • Automatic transmission transmission mode button
  • Suspension button group (with CODE 488 (Steel/air suspension) or CODE 489 (AIRMATIC (air suspension with continuously adjustable damping)))
• Direct actuation:
  • Surround lamp in inside mirror
  • Rear dome lamp ambiance illumination (via the overhead control panel electronics without CODE 414 (Power glass tilting/sliding roof))
  • Cigarette lighter with front ashtray illumination (with CODE 301 (Ashtray package/smoker package))
  • Exterior lights switch
• Actuation via the instrument panel circuit 58d connector sleeve (Z50/1):
  • Left center air outlet symbol illumination
  • Left front side air outlet symbol illumination
  • Right front side air outlet symbol illumination
  • Right center air outlet symbol illumination
• Actuation via the vehicle interior circuit 58d connector sleeve (Z51/6):
  • Rear vent symbol illumination (with CODE 581 (Comfort automatic air conditioning))
  • Center console armrest stowage compartment switch and controls illumination

In addition, the front SAM control unit sends the circuit 58d signal via chassis CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013) to the steering column tube module control unit.

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

• Actuation via steering LIN and steering wheel electronics:
  • Left multifunction steering wheel button group
  • Right multifunction steering wheel button group
• Direct actuation:
  • DIRECT SELECT lever

The overhead control panel control unit (with CODE 414 (Power glass tilting/sliding roof)) directly controls the rear dome lamp ambiance illumination.

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 active multicontour seat control unit directly actuates the driver active multicontour seat button group (with CODE 432 (Active multicontour seat)).

The right front active multicontour seat control unit directly actuates the front passenger active multicontour seat button group (with CODE 432 (Active multicontour seat), without CODE 494 (USA version)).

The left front door control unit actuates the following components:

• Actuation via left front door LIN:
  • Driver-side power window and outside mirror adjustment switch group
  • Left front switch group, seat adjustment (with CODE 275 (Memory package for electrically adjustable front seats))
• Direct actuation:
  • Left front door door handle illumination
  • Trunk lid release button (on model 218.3 without CODE 881 (Remote trunk closing (RTC)))
  • Driver trunk lid/liftgate control button (on model 218.3 with CODE 881 (Remote trunk closing (RTC)) or model 218.9)
  • Left front door central locking interior switch

The right front door control unit actuates the following components:

• Actuation via right front door LIN:
  • Right front switch group, seat adjustment (with CODE 275 (Memory package for electrically adjustable front seats))
• Direct actuation:
  • Right front door door handle illumination
  • Passenger-side power window switch
  • Right front door central locking interior switch

The left rear door control unit actuates the following components:

• Actuation via left rear door LIN:
  • Left rear seat heaters button via left rear door analog/digital converter (with CODE 872 (Electric seat heater for left and right rear seat))
• Direct actuation:
  • Left rear door door handle illumination
  • Left rear power window switch

The right rear door control unit actuates the following components:

• Actuation via right rear door LIN:
  • Left rear seat heaters button via right rear door analog/digital converter (with CODE 872 (Electric seat heater for left and right rear seat))
• Direct actuation:
  • Right rear door door handle illumination
  • Right rear power window switch

The door handle illumination, the ambient lamp and the rear dome lamp ambiance illumination are actuated at a defined value if circuit 15R is On and there is an implausible circuit 58d signal. The circuit status circuit 15 is transmitted by the electronic ignition lock control unit via the interior CAN to the respective control units.

Additional function requirements for ambiance illumination (with CODE 877 (Ambiance illumination)) 

• Circuit 15R ON
• Rain/light sensor signals "Darkness detected"
• Illumination intensity of ambiance illumination set

Function sequence for ambiance illumination (with CODE 877 (Ambiance illumination)) 

The ambiance illumination encompasses the illumination of the footwells, the trim piece at the instrument panel, the center console and the trim pieces at the vehicle doors.

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

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

• Data of rain/light sensor via wiper/inside rearview mirror LIN
• Status of circuit 15 from electronic ignition lock control unit via interior CAN
• Status of ambiance illumination brightness from instrument cluster via interior CAN

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

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

The front SAM control unit actuates the following components:

• Center console ambiance illumination
• Driver-side instrument panel ambiance illumination
• Passenger-side instrument panel ambiance illumination

The left front door control unit directly actuates the left front door ambiance illumination.

The right front door control unit directly actuates the right front door ambiance illumination.

The left rear door control unit directly actuates the left rear door ambiance illumination.

The right rear door control unit directly actuates the right rear door ambiance illumination.

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

• Right front footwell lamp
• Left front footwell lamp
• Left rear footwell lamp
• Right rear 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. The function is deactivated when the central locking is locked. The status of the vehicle doors is read in by the front SAM control unit via interior CAN as follows.

• Status of left front door rotary tumbler switch in left front door lock from left front door control unit
• Status of right front door rotary tumbler switch in right front door lock from right front door control unit
• Status of left rear door rotary tumbler switch in left rear door lock and status of right rear door rotary tumbler switch in right rear door lock from rear SAM control unit

The electronic ignition lock control unit sends the status of the central locking to the front SAM control unit via interior CAN.

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

Search and symbol illumination electrical function schematic		PE82.20-P-2054-97XAA
Electrical function schematic ambiance illumination	MODEL 218 with CODE 877 (ambient lighting)	PE82.20-P-2053-97XAA
Overview of interior illumination (IBL) system components		GF82.20-P-9997FQ