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

MODEL 166 as of model year 2016 

MODEL 292 

Block diagram 

Function requirements, general 

• No overvoltage or undervoltage (operating voltage range U ≥ 8, 5 ≤ 17 V)

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 switch and controls and symbol illumination 
• Function sequence for ambient illumination (with CODE 876 (Interior lights package)) 

Additional function requirements, search and symbol illumination 

• Standing light ON (circuit 58 ON)

Function sequence for switch and controls and symbol illumination 

In order to control the switch and controls and symbol illumination, the COMAND controller unit reads in the following signals and evaluates them:

• Status of standing lights actuation sent to the interior CAN by the SAM control unit
• Status of instrument illumination brightness control (continuous adjustment of switch and controls and symbol illumination brightness) sent by the instrument cluster via the interior CAN

If the ambient illumination function is activated via the COMAND controller unit, 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. The "standing lights actuation active" status is canceled, and the COMAND controller unit therefore deactivates the switch and controls and symbol illumination.

The controls in the vehicle are illuminated again only after circuit 15R is then switched on.

The COMAND controller unit uses the incoming data to generate the circuit 58d signal and transmits it to the actuation for the switch and controls and symbol illumination via the interior CAN to the following control units:

• SAM control unit
• Automatic air conditioning control and operating unit
• Left front door control unit
• Right front door control unit
• Left rear door control unit
• Right rear door control unit
• RCP [HBF] control unit (with CODE 581 (Automatic air conditioning) or with CODE 872 (Seat heater in rear))
• Electronic ignition switch control unit

The radio (with CODE 505 (Radio 20 NTG5 non-navigation-capable) or with CODE 522 (Audio 20 radio)) or the COMAND controller unit (with CODE 531 (COMAND APS)) sends the circuit 58d signal via the telematics CAN to the Audio/COMAND control panel.

The SAM control unit actuates the following components:

• Actuation via center console switch-LIN:
  • Lower control panel control unit
  • Off-road control panel control unit (with CODE 430 (On & off-road package))
• Actuation via roof LIN:
  • Overhead control panel control unit
• Actuation via battery sensor LIN:
  • Upper control panel control unit
• Actuation via the instrument panel circuit 58d connector sleeve (Z50/1):
  • Exterior lights switch
  • Electric parking brake switch
• With CODE 876 (Interior lights package):
  • 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 center console wiring harness connector sleeve, circuit 58d (Z61/7):
  • Front center console cup holder illumination (with CODE 876 (Interior lights package) and without CODE 311 (Temperature-controlled cup holder))
  • Center console armrest stowage compartment switch and controls illumination
  • Ashtray illumination (with CODE 301 (Smoker's package))
  • Cup holder illumination (with CODE 876 (Interior lights package) and CODE 311 (Temperature-controlled cup holder))
  • Cup holder button (with CODE 311 (Temperature-controlled cup holder))

The overhead control panel control unit actuates the following components:

• Direct actuation:
  • Ambient lamp
  • Rear dome lamp (with CODE 876 (Interior lights package))
  • Anti-theft alarm system/emergency call system button group (with CODE 882 (Interior monitoring) or CODE 348 (Emergency call/assist system))

The automatic air conditioning control and operating unit directly actuates the switch and controls and symbol illumination of the integrated controls.

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))
• Direct actuation:
  • Left front door door handle illumination
  • Driver trunk lid/liftgate control button
  • Vent window switch
  • 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 P64 (Memory package))
• 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:

• Direct actuation:
  • Left rear door door handle illumination
  • Left rear power window switch

The right rear door control unit actuates the following components:

• Direct actuation:
  • Right rear door door handle illumination
  • Right rear power window switch

The door handle illumination is actuated with a fixed dimming value with circuit 15R ON and implausible circuit 58d signal. The electronic ignition lock control unit transmits the status of circuit 15 via the interior CAN to the relevant control units.

The RCP [HBF] control unit (with CODE 581 (Automatic air conditioning) or CODE 872 (Seat heater in rear)) directly actuates the switch and controls and symbol illumination of the integrated controls.

The electronic ignition lock control unit transmits the circuit 58d signal via chassis CAN 1 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

Additional function requirements for ambient illumination (with CODE 876 (Interior lights package)) 

• Circuit 15R ON
• Illumination intensity of ambiance illumination set
• Circuit 58d from instrument cluster

Function sequence for ambient illumination (with CODE 876 (Interior lights package)) 

The ambiance illumination encompasses the illumination of the footwells, the trim pieces 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 at the COMAND controller unit.

The illumination color of the ambiance illumination can be adjusted in 3 color stages (solar, polar, and neutral) using the "Settings" menu at the COMAND controller unit.

The illumination intensity of the ambiance illumination cannot be set at the COMAND controller unit as long as one of the vehicle's doors is open.

In this case, the ambiance illumination can only be completely deactivated in the COMAND controller unit.

The following signals are read in and evaluated by the SAM control unit in order to control the ambiance illumination:

• Status of circuit 15, transmitted by the electronic ignition lock control unit via the interior CAN
• Status of ambiance illumination brightness sent by the COMAND controller unit via the interior CAN

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

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

The rear control unit actuates the following components:

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

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

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

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

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

In addition, the following components of the footwell illumination are actuated in a dimmed state while driving:

• Left front footwell lamp from SAM control unit
• Right front footwell lamp from SAM control unit
• Left rear footwell lamp from driver seat control unit
• Right rear footwell lamp from front passenger seat control unit

When the vehicle is unlocked using the central locking system, the ambiance illumination components are actuated at a set brightness setting. The opening of a vehicle door triggers the actuation of the ambiance illumination at 100 % of the possible illumination intensity.

After closing the vehicle doors, the ambiance illumination components are actuated again at the previously set illumination intensity.

Upon locking the central locking, the function is deactivated following a run-on time of t = 3 s.

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