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MODULAR CONTROL SYSTEM (MCS), FUNCTION - GF82.85-P-0011GI 
MODEL 163 as of 1.9.01 with CODE (522) Modular control system (MCS) radio USA with CODE (357) 
Navigation system - additional unit with CODE (818b) Single CD player - additional unit with CODE 
(819) 6-disk CD changer in trunk with CODE (491) U.S. version  
The following systems can be operated centrally with the aid of the radio and navigation unit (A2/56) : 
Cassette deck  
Radio  
Single CD player and CD player with changer (optional)  
Sound system (optional)  
Navigation (optional)  
Telephone (optional) 
Fig. 82: Identifying Radio And Navigation Unit
of two components: 
CTEL antenna 
(A2/49a1)  
GPS antenna 
(A2/49a2)  
  Model 163 as of 01.09.01GF82.70-P-4111-03GH
 GPS/CTEL roof antenna, 
functionCode 351 or code 353, 
except models 
129 /163 /220GF82.70-P-4111-04A
  Code 353 for model 163GF82.70-P-4111-04D
  Code 347 or 348 or 352 
except models 168/163GF82.70-P-4111-04B
  Model 163 as of 01.09.01GF82.70-P-4111-04GH
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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Fig. 83: MCS System Block Diagram 
MCS system  
The radio and navigation unit (A2/56) is the central component of the MCS system . It has a video-capable 5" 
active matrix TFT display for indicating information such as control menus and map data for navigation. 
Actuation is accomplished in operating modes NTSC (US standard) PAL (ECE standard). It is operated with 
fixed function keys and a rotary knob, a joystick as well as with menu-guidance on the display. 
The basic version of the radio and navigation unit (A2/56) is equipped with 
a radio reception unit,  
a compact cassette player and  
a speed-dependent volume control.  
Diagnostic interface  
To read out actual values and DTC's of the MCS and components connected via the digital data bus ( D2B ) 
diagnosis with the hand-held tester is possible via a K-line. 
MCS bus system  
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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The digital components of the radio and navigation unit (A2/56)are interlinked via the digital data bus 
( D2B ). Control data, audio signals and other information are transmitted between the various system 
components via the digital data bus ( D2B ) Since some of the individual components operate with various data 
formats or place different requirements on the transmission speed and transmission security, various bus 
systems are installed. 
MODULAR CONTROL SYSTEM (MCS) FUNCTION DESCRIPTION CONTENTS - GF82.85-P-0995GIZ 
MODEL 163 as of 1.9.01 with CODE (522) Modular control system (MCS) radio USA with CODE (357) 
Navigation system - additional unit with CODE (818b) Single CD player - additional unit with CODE 
(819) 6-disk CD changer with CODE (491) U.S. version  
 Switch on/off behavior, 
function GF82.85-P-2006GI
 Radio operation, function GF82.60-P-2001GI
 CD-player mode, function GF82.60-P-2002GI
 Telephone mode, function GF82.85-P-2007GI
 Cassette mode, function GF82.85-P-2010GI
 Navigation mode, function GF82.85-P-2012GI
 Volume/tone adjustments, 
function GF82.60-P-2003GI
 Radio/navigation unit 
location/task/design/ function GF82.61-P-4109GI
 Modular control system (MCS), 
function* for USA onlyGF82.85-P-0011GI
 Switch on/off behavior, 
function GF82.85-P-2006GI
 Radio operation, function GF82.60-P-2001GI
 CD-player mode, function GF82.60-P-2002GI
 Telephone mode, function GF82.85-P-2007GI
 Starguide, function GF82.85-P-2014GI
 Information service, function GF82.85-P-3016GI
 Data transmission for 
Starguide, function GF82.85-P-3017GI
 Cassette mode, function GF82.85-P-2010GI
 Navigation mode, function GF82.85-P-2012GI
 Voice output, function GF82.85-P-3001GI
 Volume/tone adjustments, 
function GF82.60-P-2003GI
 Constant map matching, 
function GF82.61-P-2002GI
 Basic location finding, function GF82.61-P-3006GI
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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CONTENTS, FUNCTION DESCRIPTION OF COCKPIT MANAGEMENT AND DATA SYSTEM (COMAND) - GF82.85-P-
0997GHZ 
MODEL 163  
 Global positioning system 
location finding, function GF82.61-P-3007GI
 Map-supported location 
finding, function GF82.61-P-3008GI
 Route calculation, function GF82.61-P-3011GI
 Dynamic route guidance, 
function GF82.61-P-4003GI
 Guidance, function GF82.61-P-3012GI
 Destination guidance in 
digitized map area, function GF82.61-P-4000GI
 Destination guidance in non-
digitized map area, function GF82.61-P-4001GI
 Modular control system (MCS) 
survey of system components 
location/task/design/ function GF82.85-P-9995GIZ
 Cockpit management and data system 
(COMAND) function GF82.85-P-0003GH
 Switch-on/switch-off characteristics, 
function GF82.85-P-2006GH
 Radio operation, function GF82.60-P-2001GH
 CD-player mode, function GF82.60-P-2002GH
 Volume/tone adjustments, function GF82.60-P-2003GH
 Navigation mode, function GF82.85-P-2012GH
 Constant map matching, function GF82.61-P-2002GH
 Basic location finding, function GF82.61-P-3006GH
 Global positioning system location 
finding, function GF82.61-P-3007GH
 Map-supported location finding, 
function GF82.61-P-3008GH
 Route computation, function GF82.61-P-3011GH
 Destination-finding system, function GF82.61-P-3012GH
 Destination finding in digitized map 
area, function GF82.61-P-4000GH
 Destination finding in non-digitized 
map area, function GF82.61-P-4001GH
 Dynamic destination finding, functionWith dynamic 
destination finding 
(code 815) not for GF82.61-P-4003GH
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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SWITCH ON/OFF BEHAVIOR, FUNCTION - GF82.85-P-2006B 
MODEL 163, 168, 170, 203.0 /2 /7, 208, 209.3 /4, 210 with CODE (353) Audio 30 APS  
ON/off characteristics  
The radio (A2) is switched on by pressing the "ON" button. The radio (A2) likewise switches On automatically 
by rotating the ignition key (models 163, 168, 170, 208, 210) or transmitter key (A8/1) (models 203, 209) into 
position 1 "circuit 15R ON", provided that it was switched on immediately before the last time "circuit 15R 
ON" was switched off. However, if the radio (A2) was switched off last, only the following components are 
activated with "circuit 15R ON": 
Digital databus (D2B)  
Continuous location finding  
In this case the display on the radio (A2) remains Off. This allows quick availability of the system when the 
"ON" button is then actuated. 
Following each switch-on operation, the system returns to the state in which it was before it was last switched 
off (e.g. navigation basic menu). 
 The bus systems and navigation processor for location finding (for quicker readiness for operation) are 
already activated when the driver door is opened. 
Switch off characteristics  
The system is switched off by switching off at the "ON" button or when "circuit 15R ON" is switched off. 
The unit switches off automatically after an hour, if when switching on the ignition key (models 163, 168, 170, 
208, 210) or transmitter key (A8/1) (models 203, 209) has not been inserted in the ignition switch. 
Run-on time/navigation  
 
 CTEL mode, functionFor MB CTEL 
standard (code 853) 
or MB portable 
CTEL (code 854).GF82.85-P-2007GH
 Voice command, function GF82.85-P-3001GH
 Table of contents, function description 
of antenna system (ATS) GF82.62-P-0999B
 Overview of system components for 
cockpit management and data system 
(COMAND ), 
location/task/design/function GF82.85-P-
9997GHZ
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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The data on the current navigation are stored for 12 hours after the radio (A2) is switched off. 
SWITCH-ON/OFF CHARACTERISTICS, FUNCTION - GF82.85-P-2006GI 
MODEL 163 as of 1.9.01 with CODE (522) Modular control system (MCS) radio USA with CODE (357) 
Navigation system - additional unit with CODE (818b) Single CD player - additional unit with CODE 
(491) U.S. version  
Switch-on characteristics  
Activation of entire system  
When the ignition/starter switch is turned to position 1(c.15R, ON ) the display is switched on , if the radio 
and navigation module (A2/56) has been switched on before the ignition key was removed the last time. 
The radio and navigation module (A2/56) is now ready for operation. The system active before the last 
switch-off (e.g. radio) is switched on and the corresponding basic menu displayed. If the radio and navigation 
module (A2/56) has been switched off for longer than 60 min a warning display appears with general 
specifications for using the system. 
 When a telephone call is received the radio and navigation module (A2/56) switches on automatically. 
Behavior when rotary knob is pressed  
The radio and navigation module (A2/56) can also be switched on the when the remote control ke
y (A8/1) is 
removed by actuating the rotary knob. 
All functions are then available for 60 min . After expiration of 60 min the radio and navigation module 
(A2/56) switches off automatically. 
This function can only be repeated by actuating the rotary knob again. 
Switch-off characteristics  
The radio and navigation module (A2/56) can be switched off by turning the ignition key to position 0 c. 15C, 
OFF ). 
 Radio operation, function GF82.60-P-2001B
 CD-player mode, 
function GF82.60-P-2002B
 Telephone mode, 
functionModel 209GF82.85-P-2007QA
 Navigation mode, 
functionModel 163, 168, 
170,208,210GF82.85-P-2012B
  Model 203, 209GF82.85-P-2012EE
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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When the rotary knob is actuated in the switched-on state the radio and navigation module (A2/56)can be 
switched off. 
Switch-off characteristics when voltage is too low  
The central processor in the radio and navigation module (A2/56) permanently monitors the battery voltage. 
Depending on the voltage value the system will act as follows: 
The battery voltage less than 9.5 volts  
If the battery voltage drops below 9.5 volts the radio and navigation module (A2/56) switches off 
automatically. 
If the system switches off and the voltage increases to greater than 9.5 volt the radio and navigation module 
(A2/56) does not switch back on automatically.  
If the system switches off it can be switched back on manually . 
TELEPHONE MODE, FUNCTION - GF82.85-P-2007GI 
MODEL 163 as of 1.9.01 with CODE (522) Modular control system (MCS) radio USA with CODE (357) 
Navigation system - additional unit with CODE (818b) Single CD player - additional unit with CODE 
(491) U.S. version  
 Radio mode, function GF82.60-P-2001GI
 CD-player mode, 
function GF82.60-P-2002GI
 Telephone mode, 
function GF82.85-P-2007GI
 Cassette mode, function GF82.85-P-2010GI
 Navigation mode, 
function GF82.85-P-2012GI
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
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Fig. 84: MCS Telephone System Block Diagram 
The telephone system can be operated as follows: 
directly on the radio and navigation module (A2/56) or  
with the portable cellular telephone (A34/6) or  
with the telephone handset (A34)  
Making a call, function  
The data telegrams (e.g. button actuation) for controlling the telephone system are relayed to the telephone 
transmitter/receiver (A35) from the radio and navigation module (A2/56) via the digital data bus ( D2B ) 
The actual telephone connection is completed by the CTEL/GPS antenna splitter (A2/57) and the CTEL and 
GPS roof antenna (A2/49)  
The audio source is automatically muted during a telephone call. 
After switching over to the telephone mode the following display appears: 
Strength of received signal (illustrated with 5 beams )  
Message indicating readiness for telephone mode with "Ready" display. 
 
2001 Mercedes-Benz ML320 
1998-2005 ACCESSORIES & BODY, CAB Electrical System - Body - 163 Chassis  
me  
Saturday, October 02, 2010 3:30:06 PMPage 137 © 2006 Mitchell Repair Information Company, LLC.