Mercedes-Benz R-Class (W251) – fuse box diagram

Mercedes-Benz R-Class (W251) – fuse box diagram

Year of production:

Fuse Box in Luggage Compartment

to 31.05.2006

Mercedes-Benz R-Class - (W251) - fuse box diagram - luggage compartment
Mercedes-Benz R-Class – (W251) – fuse box diagram – luggage compartment

as of 01.06.2006

Mercedes-Benz R-Class - (W251) - fuse box diagram - luggage compartment
Mercedes-Benz R-Class – (W251) – fuse box diagram – luggage compartment
Number Description Ampere ratting [a]
20 Interference suppression filter for radio antenna
Microphone array control unit (up to 2008; except Japan version)
Voice control system (VCS [SBS]) control unit (up to 2008; USA version
5
21 RCP [HBF] control unit 5
22 Parktronic system (PTS) control unit
Stationary heater (STH) radio remote control receiver (as of 2009)
5
23 DVD player (rear entertainment system)
E-net compensator
Rear audio control unit (up to 2008)
Portable CTEL separation point (up to 2008; Japan version)
Universal Portable CTEL Interface (UPCI [UHI]) control unit (up to 2008; Japan version)
COMAND operating, display and controller unit (as of 2009)
10
24 Right front reversible emergency tensioning retractor 40
25 up to 2008:
Radio (except USA version and Japan version)
Radio and navigation unit (except USA version and Japan version)
COMAND operating, display and controller unit
15
as of 2009:
Radio
Radio and navigation unit
COMAND operating, display and controller unit
20
26 Right front door control unit 25
27 Front passenger seat adjustment comfort relay (up to 2008)
Passenger-side front seat adjustment control unit with memory
30
28 Driver seat adjustment comfort relay (up to 2008)
Driver-side front seat adjustment control unit, with memory
30
29 Left front reversible emergency tensioning retractor 40
30 up to 2008:
Valid for engine 156:
Left fuel pump control unit
Right fuel pump control unit
as of 2009: Fuel system control unit
40
31 HS [SIH], seat ventilation and steering wheel heater control unit 10
32 AIRmatic with ADS control unit
Rear axle level control system control unit
15
33 Keyless Go control unit 25
34 Left front door control unit 25
35 Amplifier for sound system
Subwoofer amplifier (as of 2009)
30
36 up to 2008: Emergency call system control unit 5
up to 2008:
   Japan version:
VICS+ETC voltage supply separation point
as of 2009: Emergency call system control unit
10
37 Backup camera voltage supply module (as of 01.06.2006, except USA version and Japan version)
Backup camera control unit (as of 01.06.2006, Japan version)
5
38 Audio gateway control unit (up to 2008; Japan version)
Digital TV tuner
TV combination tuner (analog/digital)
10
39 up to 2008:
   SDAR control unit (USA version)
Tire pressure monitor (TPM) [RDK] control unit
as of 2009:
Tire pressure monitor (TPM) [RDK] control unit
High definition tuner control unit
Digital Audio Broadcasting control unit
External navigation separating point (South Korea version)
7,5
40 up to 2008: Rear-end door closing control unit 40
as of 2009: Rear-end door closing control unit 30
41 Overhead control panel control unit 25
42 Overhead control panel control unit 25
43 Up to 31.05.2006:
Tailgate wiper motor
Left 3rd seat row socket
Right 3rd seat row socket
as of 2009:
Valid for engine 272, 273, 276: Fuel system control unit
Valid for engine 642.872: Right fuel system control unit
20
44 Up to 31.05.2006:
Left 2nd seat row socket
Right 2nd seat row socket
as of 2009:
USA version:
Front interior socket
115 V socket
20
45 up to 2008:
Cargo area connector box
up to 31.05.2006:
Front interior socket
as of 01.06.2006:
Left 2nd seat row socket
Right 2nd seat row socket
as of 2009:
Right 2nd seat row socket
Luggage compartment socket
20
46 Front cigar lighter with ashtray illumination 15
47 as of 2009:
Valid for retrofit:
Left front illuminated door sill molding
Right front illuminated door sill molding
10
48 as of 2009:
Valid for engine 642.870: AdBlue® supply relay
5
49 Right antenna coil (up to 2008)
Heated rear window
30
50 up to 2008: Tailgate wiper motor 10
as of 2009: Tailgate wiper motor 15
51 Activated charcoal filter shutoff valve 5
52 up to 30.6.09:  
Left front reversible emergency tensioning retractor
Right front reversible emergency tensioning retractor
5
53 AIRmatic with ADS control unit
Rear axle level control system control unit
up to 2008:
Valid for engine 156:
Left fuel pump control unit
Right fuel pump control unit
as of 2009:
Valid for engine 272, 273, 276: Fuel system control unit
Valid for engine 642.872: Right fuel system control unit
5
54 Front SAM control unit
Headlamp range adjustment control unit (bi-xenon headlamp unit)
5
55 Rotary light switch
Instrument cluster
7,5
56 up to 2008: Data link connector
as of 2009:
Valid for engine 642.870: AdBlue® control unit
5
57 up to 2008: Fuel pump with fuel gauge sensor
as of 2009:
Valid for engine 642.870: Fuel pump
20
58 Data link connector
Central gateway control unit
7,5
59 Driver NECK-PRO head restraint solenoid
Front passenger NECK-PRO head restraint solenoid
7,5
60 up to 2008:
Glove compartment illumination with switch
Rear SAM control unit
Engine compartment fuse and relay box
CTEL separation point
VICS+ETC voltage supply separation point (Japan version)
Emergency call system control unit
as of 2009:
Glove box illumination with switch
Engine compartment fuse and relay box
Rear SAM control unit)
Cell phone separation point
VICS+ETC power supply separating point (Japan version)
Multicontour seat pneumatic pump
External navigation separating point (South Korea version)
Emergency call system control unit
Rear bumper interior Blind Spot Monitoring electrical connector
5
61 Restraint systems control unit
Right front seat contacting strip
10
62 Front passenger seat adjustment switch
Front passenger lumbar support regulator control unit
30
63 Driver seat adjustment switch
Driver lumbar support regulator control unit
30
64
65
66 as of 2009: Multicontour seat pneumatic pump 30
67 Rear air conditioning blower motor 25
68 up to 2008: Heated rear seats
as of 2009: Seat heater, seat ventilation and steering wheel heater control unit
25
69 30
70 Trailer hitch socket (13-pin)
Trailer hitch socket (7-pin) (USA version)
20
71 USA version: Electric brake control separation point 30
72 Trailer hitch socket (13-pin) 15
Relay
K to 31.05.2006: Terminal 15R power outlet relay, with power-down
as of 01.06.2006: Relay, circuit 15R sockets (with power-down) (power supply of electric seat adjustment)
L Terminal 30X
M Heated rear window relay
N Circuit 15 relay / terminal 87FW
O Fuel pump relay
P Rear wiper relay
R Circuit R relay 15R
S Reserve 1 (changer) (power supply for front socket)
T as of 01.06.2006: Reserve 2 (normally open contact) (power supply for center and rear sockets)
U as of 01.06.2006: Trailer relay terminal 30
V as of 01.06.2006: Spare relay 2

Fuse Box in Passenger Compartment

Mercedes-Benz R-Class (W251) - fuse box diagram - passenger compartment
Mercedes-Benz R-Class (W251) – fuse box diagram – passenger compartment
Number Description Ampere ratting [A]
10 Booster blower electronic blower controller 10
11 Instrument cluster 5
12 Automatic air conditioning [KLA] control and operating unit
Comfort automatic air conditioning [KLA] control and operating unit
15
13 Upper control panel control unit
Steering column module
5
14 CD changer (up to 2008)
EZS control unit
7,5
15 Electronic compass
Media interface control unit (as of 2009)
5
16
17
18

Fuse Box in Engine Compartment

Mercedes-Benz R-Class (W251) - fuse box diagram - engine compartment
Mercedes-Benz R-Class (W251) – fuse box diagram – engine compartment
Number Description Ampere ratting [A]
100 Wiper motor 30
101 up to 2008:
AAC with integrated control additional fan motor
Valid for engines 113, 272: Purge control valve
Valid for engine 272:
Radio interference suppression capacitor 1
Radio interference suppression capacitor 2
Cylinder 1 ignition coil
Cylinder 2 ignition coil
Cylinder 3 ignition coil
Cylinder 4 ignition coil
Cylinder 5 ignition coil
Cylinder 6 ignition coil
Valid for engine 642:
O2 sensor upstream of CAT
CDI control unit
as of 2009:
Engine and air conditioning electric suction fan with integrated control
Valid for engine 272, 273:
Purging switchover
Circuit 87 M1e connector sleeve
Valid with engine 642:
CDI control unit
O2 sensor upstream of CAT
Valid for engine 642.870/872:
O2 sensor upstream of CAT
15
102 up to 2008:
Valid for engine 642:
Recirculation pump for transmission oil cooler
Valid for engine 156:
Engine coolant circulation pump
as of 2009:
Valid for engine 642, engine 642.870 up to 31.7.10: 
Transmission cooler circulation pump
Valid with engine 276:
Charge air cooler circulation pump
15
103 up to 2008:
Valid for engine 113:
ME-SFI [ME] control unit
Cylinder 1 fuel injection valve
Cylinder 2 fuel injection valve
Cylinder 3 fuel injection valve
Cylinder 4 fuel injection valve
Cylinder 5 fuel injection valve
Cylinder 6 fuel injection valve
Cylinder 7 fuel injection valve
Cylinder 8 fuel injection valve
Valid for engine 642:
CDI control unit
as of 2009:
Valid for engine 642.950, 642.870/872: CDI control unit
Valid for engine 272: ME-SFI [ME] control unit
Valid with engine 276:
ME-SFI [ME] control unit
Engine/engine compartment connector
25
104 up to 2008:
Valid for engine 113:
Left O2 sensor upstream TWC [KAT]
Right oxygen O2 sensor upstream of catalytic converter
Left O2 sensor downstream TWC [KAT]
Right O2 sensor downstream TWC [KAT]
Variable intake manifold switchover valve
EGR vacuum transducer
Air pump change-over valve
Valid for engine 272:
Heating system shutoff valve
Intake manifold tumble flap switchover valve
Air pump change-over valve
Three-disk thermostat valve
Pressure regulating on the valve power steering unit pump
Valid for engine 642:
Left hot film mass air flow sensor
Right hot film mass air flow sensor
Intake port shutoff motor
Glow time output stage
Vent line heater element
Power steering pump pressure regulator valve
Left exhaust gas recirculation positioner
Boost pressure positioner
as of 2009:
Valid for engine 272, 273: Connector sleeve, circuit 87 M2e
Valid for engine 642.950: Circuit 87 connector sleeve
Valid for engine 642.870/872: Circuit 87D2 connector sleeve
15
105 up to 2008:
Valid for engine 113:
ME control unit
Radio interference suppression capacitor 1
Radio interference suppression capacitor 2
Cylinder 1 ignition coil
Cylinder 2 ignition coil
Cylinder 3 ignition coil
Cylinder 4 ignition coil
Cylinder 5 ignition coil
Cylinder 6 ignition coil
Cylinder 7 ignition coil
Cylinder 8 ignition coil
Valid for engine 272:
ME control unit
Hot film mass air flow sensor
Hall sensor for left inlet camshaft
Right intake camshaft Hall sensor
Left exhaust camshaft Hall sensor
Right exhaust camshaft Hall sensor
Left intake camshaft solenoid
Right camshaft intake solenoid
Left exhaust camshaft solenoid
Right exhaust camshaft solenoid
Cylinder 1 fuel injection valve
Cylinder 2 fuel injection valve
Cylinder 3 fuel injection valve
Cylinder 4 fuel injection valve
Cylinder 5 fuel injection valve
Cylinder 6 fuel injection valve
Valid for engine 642: CDI control unit
as of 2009:
Valid for engine 272, 273:
ME-SFI [ME] control unit
Circuit 87 M1i connector sleeve
Valid with engine 276: Engine/engine compartment connector
Valid for engine 642.950:
CDI 1.0 PK control unit
Engine compartment/interior compartment connector
Valid for engine 642.870/872:
CDI control unit
Engine compartment/interior compartment connector
Circuit 87 connector sleeve
15
106
107 Valid for engine 113, 272, 273: Electric air pump 40
108 AIRmatic compressor unit 40
109 ESP control unit 25
110 Alarm signal horn with additional batteryAlarm siren 10
111 Intelligent servo module for DIRECT SELECT 30
112 Left front lamp unit
Right front lamp unit
7,5
113 Left fanfare horn
Right fanfare horn
15
114 up to 2008:
Front SAM control unit
   Valid for engine 272: ME control unit
as of 2009: Front SAM control unit
5
115 ESP control unit 5
116 Electric controller unit (VGS) 7,5
117 Distronic (DTR) controller unit 7,5
118 Valid for engine 272, 273, 276: ME control unit
Valid for engine 642: CDI control unit
5
119 Valid for engine 642.870/872:CDI control unit 5
120 up to 2008:
Valid for engine 113, 272: ME control unit
Valid for engine 642: CDI control unit
as of 2009:
Valid for engine 272, 273, 276:
Engine circuit 87 relay
ME-SFI [ME] control unit
Valid with engine 642: Engine circuit 87 relay
10
121 STH heater unit 20
122 Valid for engine 113, 272, 273, 276, 642: Starter 25
123 Valid for diesel engine as of 1.9.08: Fuel filter condensation sensor with heating element 20
124 as of 2009: Electrohydraulic power steering 7,5
125
Relays
A Wiper stage 1 and 2 relay
B Wiper ON / OFF
C Valid for engine 642: Additional circulation pump for transmission oil cooling
Valid for engine 156: Engine coolant circulation pump
D Terminal 87 engine
E Secondary air injection pump
F Horn
G Air suspension compressor
H Circuit 15
I Starter

Battery Compartment Prefuse Box

Mercedes-Benz R-Class (W251) - fuse box diagram - battery compartment prefuse box
Mercedes-Benz R-Class (W251) – fuse box diagram – battery compartment prefuse box
Number Description Ampere ratting [A]
78 Diesel engine: Heater booster control unit 150
79 Rear SAM control unit 60
80 Rear SAM control unit 60
81 as of 2009:
Valid for engine 642.870: AdBlue® supply relay
Valid with engine 276: Engine compartment fuse and relay box
40
82 up to 2008: Load compartment fuse and relay box 150
as of 2009: Load compartment fuse and relay box 100
83 USA version: WSS (Weight Sensing System) control unit 5
84 Restraint systems control unit 10
85 as of 2009: DC/AC converter control unit (115 V socket) 25
86 Cockpit fuse box 30
87 30
88 up to 2008: Front SAM control unit 70
as of 2009: Front SAM control unit 40
89 Front SAM control unit 70
90 Front SAM control unit 70
91 Blower regulator 40

Front Prefuse

Mercedes-Benz R-Class (W251) - fuse box diagram - front prefuse
Mercedes-Benz R-Class (W251) – fuse box diagram – front prefuse
Number Description Ampere ratting [A]
4
5 Valid as of 1.7.09: ESP control unit 40
6 Valid up to 30.6.09: ESP control unit 40
Valid as of 1.7.09: Electrohydraulic power steering 100
7 A100AC with integrated control additional fan motor
8 Engine compartment fuse and relay box 150

WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.