The Mercedes-Benz C-Class W204 is a popular luxury sedan that was produced from 2008 to 2014. It is known for its sleek design, powerful engines, and luxurious interior.
One of the most important components of the C-Class W204 is the fuse box. The fuse box is responsible for protecting the electrical system of the car from damage caused by overloads or shorts.
If you own a Mercedes-Benz C-Class W204, it is important to know where the fuse box is located and how to identify the different fuses. This will help you troubleshoot electrical problems in your car and replace blown fuses as needed.
Table of Contents
There are three fuse boxes located in the Mercedes-Benz C-Class W204:
- Engine compartment fuse box: This fuse box is located in the engine compartment, on the left side of the car.
- Passenger compartment fuse box: This fuse box is located under the dashboard, on the driver’s side.
- Luggage compartment fuse box: This fuse box is located in the luggage compartment, on the left side.
Let’s explore all the fuse boxes in the C-Class W204.
Fuses and relays in the Engine Compartment
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 1 | Electronic Stability Program control unit | 25 |
| 2 | Left front door control unit | 30 |
| 3 | Valid up to 31.3.10: Right front door control unit Valid as of 1.4.10 with model 204.0/2/9: Right rear door control unit | 30 |
| 4 | up to 31.8.08: Fuel pump control unit Valid for engine 156 up to 31.8.08: Left fuel pump control unit Right fuel pump control unit Valid for engine 642, engine 651: Fuel filter condensation sensor with heating element Valid for engine 651 up to 31.5.10, engine 646: Control unit for fuel filter condensation sensor with heating element | 7.5 |
| 4 | Valid for diesel engine as of 1.9.08: Fuel filter condensation sensor with heating element Valid for engine 276 (USA, South Korea): Activated charcoal canister shutoff valve Valid for model 204.0/2/3 as of 1.3.11, 204.9 as of 1.6.12: Headlamp control unit | 20 |
| 5 | Rear SAM control unit with fuse and relay module Valid as of 1.6.10 Exterior lights switch Valid for engine 156 Black Series as of 1.7.11: Rear axle differential coolant circuit relay | 7.5 |
| 6 | Valid for diesel engine: ME-SFI [ME] control unit Valid for gasoline engine: CDI control unit | 10 |
| 7 | Starter | 20 |
| 8 | Supplemental restraint system control unit | 7.5 |
| 9 | Glove compartment power outlet | 15 |
| 10 | Wiper motor | 30 |
| 11 | Audio/COMAND display Audio/COMAND control panel Holder for navigation module | 7.5 |
| 12 | Automatic air conditioning control and operating unit Upper control panel control unit | 7.5 |
| 13 | Steering column module control unit Multifunction camera | 7.5 |
| 14 | Electronic Stability Program control unit | 7.5 |
| 14 | Headlamp control unit | 20 |
| 15 | Supplemental restraint system control unit | 7.5 |
| 16 | Diagnostic connector (up to 31.5.09) Mobile phone electrical connector Valid for transmission 722: Electronic selector lever module control unit | 5 |
| 16 | ECO start/stop function: Electric transmission oil pump | 20 |
| 17 | Panoramic sliding roof control module Overhead control panel control unit | 30 |
| 18 | Valid up to 30.11.09: Exterior lights switch Valid for model 204.0/2 as of 1.3.11, model 204.3: Upper control panel control unit Valid for model 204.0/2 up to 28.2.11, model 204.9: Instrument panel climate control LIN positive line connector sleeve Vehicle interior and harness for taillamp electrical connector | 7.5 |
| 19 | Electric steering lock control unit Electronic ignition lock control unit | 20 |
| 20 | Electronic Stability Program control unit | 40 |
| 21 | Stop lamp switch Glove compartment lamp switch Front passenger seat occupied recognition and ACSR Electronic Toll Collection preinstallation electrical fuse (Japan) | 7.5 |
| 22 | Combustion engine fan motor and air conditioning with integrated control Electrical connector for interior harness and engine wiring harness | 15 |
| 23 | Electrical connector for interior harness and engine wiring harness Valid for diesel engine: Rear SAM control unit with fuse and relay module CDI control unit Terminal 87 connector sleeve Valid for engine 271: Terminal 87 M1e connector sleeve Valid for engine 272: Circuit 87 M1i connector sleeve | 20 |
| 24 | Electrical connector for interior harness and engine wiring harness Interior and engine wiring harness electrical connector Valid for engine 642: Radiator shutters actuator Valid for engine 272: Terminal 87 M1e connector sleeve Valid for diesel engine: Terminal 87 connector sleeve Valid for engine 646: CDI control unit | 15 |
| 25 | Valid for engine 156, 271, 272, 274, 276: ME-SFI [ME] control unit Valid for diesel engine: Oxygen sensor upstream of catalytic converter Valid as of 1.6.10 for model 204.3 with engine 651 Sport Edition: Exhaust system sound generator control unit | 15 |
| 26 | Radio Radio with auto pilot system COMAND controller unit | 20 |
| 27 | Electric steering lock control unit Electronic ignition lock control unit Valid for diesel engine: CDI control unit Valid for gasoline engine: ME-SFI [ME] control unit | 7.5 |
| 28 | Instrument cluster | 7.5 |
| 29 | Right front lamp unit | 10 |
| 30 | Left front lamp unit Valid for engine 642: Electrical connector for interior harness and engine wiring harness | 10 |
| 31A | Left fanfare horn Right fanfare horn | 15 |
| 31B | Left fanfare horn Right fanfare horn | 15 |
| 32 | Valid for engine 156, 271, 272, 276: Electric air pump | 40 |
| 32 | Valid for engine 156: Oil cooler fan motor | 20 |
| 33 | Valid for transmission 722.6: Electronic transmission-control control unit Valid for transmission 722.9: Fully integrated transmission control controller unit | 10 |
| 34 | Valid for engine 271, 272 as of 1.9.08: Fuel pump control unit Valid for engine 156 as of 1.9.08: Left fuel pump control unit, Right fuel pump control unit | 7.5 |
| 35 | Valid as of 1.3.11: Electronic Stability Program control unit | 5 |
| 36 | Valid as of 1.3.11: DISTRONIC electric controller unit Valid for model 204.902/982/984: Electrohydraulic power steering | 7.5 |
| Relay | ||
| J | Circuit 15 relay | |
| K | Terminal 15R relay | |
| L | Backup relay | |
| M | Circuit 50 starter relay | |
| O | Engine circuit 87 relay | |
| O | Fanfare horn relay | |
| P | Valid for engine 156, 272, 276: Secondary air injection relay | |
| Q | Backup relay | |
| R | Chassis circuit 87 relay |
Front Pre-fuse Box (Model years up to 2010)
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 88 | Pyrofuse: Alternator, Starter | |
| 89 | Front SAM control unit with fuse and relay module | 125 |
| 90 | Rear SAM control unit with fuse and relay module | 40 |
| 91 | Combustion engine fan motor and air conditioning with integrated control | 80 |
| 100 | Air conditioner housing | 40 |
| 101 | Valid for gasoline engine: Front SAM control unit with fuse and relay module | 60 |
| 103 | Valid for diesel engine: PTC heater booster | 150 |
| 104 | Interior fuse box | 70 |
| 105 | Front SAM control unit with fuse and relay module | 100 |
| 106 | Rear SAM control unit with fuse and relay module | 150 |
| 107 | Spare | – |
| 108 | Spare | – |
| 109 | Spare | . |
| 110 | Spare | – |
Front Prefuse Box (as of 2010)
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 150 | without ECO start/stop: Pyrofuse 88 | 400 |
| 150 | ECO start/stop: Alternator, Starter | 200 |
| 151 | Combustion engine fan motor and air conditioning with integrated control | 100 |
| 152 | Front SAM control unit with fuse and relay module | 150 |
| 153 | without ECO start/stop: Spare | 100 |
| 153 | ECO start/stop function and front battery position: Front SAM control unit with fuse and relay module | 60 |
| 154 | ECO start/stop function and front battery position: Front SAM control unit with fuse and relay module | 60 |
| 154 | Valid for diesel engine and ECO start/stop: PTC heater booster | 150 |
| 155 | without ECO start/stop: Spare | 50 |
| 155 | ECO start/stop function: Spare | 100 |
| 156 | Valid for diesel engine without ECO start/stop: PTC heater booster | 150 |
| 156 | ECO start/stop function: Front SAM control unit with fuse and relay module | 100 |
| 157 | Valid for model 204.902/982/984 without ECO start/stop function: Electrohydraulic power steering ECO start/stop: Spare | 100 |
| 158 | without ECO start/stop: Blower regulator | 50 |
| 158 | ECO start/stop: Rear SAM control unit with fuse and relay module | 150 |
| 159 | Special-purpose vehicle multifunction control unit | 50 |
| 159 | ECO start/stop: Additional battery relay | 200 |
| 160 | without ECO start/stop: Spare | 60 |
| 160 | ECO start/stop: Blower regulator | 50 |
| 161 | without ECO start/stop: Front SAM control unit with fuse and relay module | 100 |
| 161 | Special-purpose vehicle multifunction control unit | 50 |
| 162 | without ECO start/stop: Spare | 100 |
| 162 | ECO start/stop: Spare | 60 |
| 163 | without ECO start/stop: Rear SAM control unit with fuse and relay module | 150 |
| 164 | without ECO start/stop function: Rear SAM control unit with fuse and relay module | 80 |
Fuses in the Instrument Panel
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 116 | Driver seat control unit | 30 |
| 117 | Adaptive damping system control unit | 15 |
| 118 | Spare | – |
| 119 | Rear blower motor AMG Performance Media control unit (valid as of 1.6.12) | 7.5 |
| 120 | Spare | – |
| 121 | Spare | . |
| 122 | Spare | – |
| 123 | Steering column tube module control unit | 10 |
| 124 | Spare | . |
| 125 | Spare | – |
| 126 | Front passenger seat control unit | 30 |
| 127 | Spare | – |
| 128 | Spare | . |
| 129 | Valid for engine 156: Oil cooler fan motor relay | 20 |
| 130 | Spare | . |
| 131 | Spare | – |
| 132 | Spare | – |
| 133 | Spare | . |
| 134 | Spare | – |
| 135 | Spare | – |
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 37 | as of 2008: Driver seat NECK-PRO head restraint solenoid, Front passenger seat NECK-PRO head restraint solenoid | 5 |
| 37 | up to 2008: Driver seat NECK-PRO head restraint solenoid, Front passenger seat NECK-PRO head restraint solenoid | 7.5 |
| 38 | Tailgate wiper motor | 15 |
| 39 | Valid for model 204.0/2/9 except vehicles for Great Britain up to 31.5.09: Left rear door control unit | 30 |
| 40 | Spare | – |
| 41 | Valid for model 204.0/2/9 up to 31.3.10: Right rear door control unit Valid as of 1.4.10 Right front door control unit | 30 |
| 42 | Valid for gasoline engine or engine 642 as of 1.12.09 or engine 651 as of 1.6.09: Fuel pump control unit | 25 |
| 42 | Valid for engine 646 or engine 642 up to 30.11.09 or engine 651 up to 31.5.09: Fuel pump Valid for gasoline engine (up to 2009): Fuel pump control unit | 20 |
| 43 | Valid as of 1.6.09 with automatic air conditioning: Rear blower motor | 5 |
| 44 | Switch group, right front seat setting Front passenger seat partially electric seat adjustment switch | 30 |
| 45 | Left front seat adjustment switch group Driver seat partially electric seat adjustment switch | 30 |
| 46 | Antenna amplifier for rear window FM antenna Alarm siren Interior protection and tow-away protection control unit Rear window antenna amplifier 1 TV 1 antenna amplifier and DAB Band III DAB band III antenna TV 2 antenna amplifier and KEYLESS-GO KEYLESS-GO antenna amplifier | 7.5 |
| 47 | Spare | – |
| 48 | Spare | – |
| 49 | Rear window heater | 40 |
| 50 | Right front reversible emergency tensioning retractor | 50 |
| 51 | Left front reversible emergency tensioning retractor (A76) | 50 |
| 52 | Spare | – |
| 53 | as of 2008: Trailer recognition control unit | 15 |
| 53 | up to 2008: Trailer recognition control unit | 30 |
| 54 | up to 31.5.09: Trailer recognition control unit Valid for model 204.075/077/275/277: Driver seat lumbar support and side bolster adjustment switch group Front passenger seat lumbar support and side bolster adjustment switch group Front passenger seat AMG valve block Driver seat AMG valve block | 7.5 |
| 54 | as of 1.6.09: Trailer recognition control unit | 15 |
| 55 | Valid as of 1.6.09: AdBlue | 5 |
| 56 | Trailer recognition control unit Trailer socket | 15 |
| 56 | Valid for model 204.077/277/377 up to 31.5.09: Driver seat lumbar support and side bolster adjustment switch group Front passenger seat lumbar support and side bolster adjustment switch group Front passenger seat AMG valve block Driver’s seat AMG valve block | 5 |
| 57 | Trailer recognition control unit | 20 |
| 58 | as of 2008: Trailer recognition control unit | 20 |
| 58 | up to 2008: Trailer recognition control unit | 30 |
| 59 | as of 2008: Parking system control unit Left front bumper DISTRONIC (DTR) sensor Right front bumper DISTRONIC (DTR) sensor Intelligent radar sensor for left rear bumper Intelligent radar sensor for right rear bumper | 5 |
| 59 | up to 2008: PARKTRONIC control unit Radar sensors control unit | 7.5 |
| 60 | Multicontour seat pneumatic pump | 7.5 |
| 61 | Liftgate-control control unit | 40 |
| 62 | Driver seat control unit | 30 |
| 63 | Front passenger seat control unit | 30 |
| 64 | DC/AC converter control unit | 25 |
| 65 | Adaptive damping system control unit Steering column tube module control unit | 15 |
| 66 | Spare | – |
| 67 | as of 2008: Sound system amplifier control unit | 30 |
| 67 | up to 2008: Sound system amplifier control unit | 40 |
| 68 | Spare | . |
| 69 | Rear bass speaker amplifier | 20 |
| 70 | Tire pressure monitor control unit | 5 |
| 71 | Front cigarette lighter with ashtray illumination Front vehicle interior power outlet | 15 |
| 72 | Cargo area connector box 115 V power outlet | 15 |
| 73 | Diagnostic connector (as of 1.6.09) Stationary heater radio remote control receiver Valid for engine 156 as of 1.7.11: Transmission mode control unit | 7.5 |
| 74 | KEYLESS-GO control unit | 15 |
| 75 | Stationary heater unit | 20 |
| 76 | Vehicle interior power outlet | 15 |
| 77 | Weight Sensing System (WSS) control unit | 7.5 |
| 78 | Left front seat ventilation blower regulator Right front seat ventilation blower regulator | 7.5 |
| 79 | Parking system control unit | 5 |
| 80 | Video and radar sensor system control unit Parking system control unit | 7.5 |
| 81 | Media interface control unit | 5 |
| 82 | Cellular telephone system compensator UMTS TV tuner control unit (up to 31.5.09; Japan) Digital TV tuner (up to 31.5.09; Japan) | 5 |
| 83 | Electronic Toll Collection control unit (Japan) Emergency call system control unit Reversing camera Left rear display Right rear display | 7.5 |
| 84 | Satellite digital audio radio (SDAR) control unit SDAR/high definition tuner control unit Digital Audio Broadcasting control unit Backup camera power supply module Backup camera control unit 360° camera control unit | 7.5 |
| 85 | TV tuner control unit (up to 31.5.09; Japan) Digital TV tuner (as of 1.6.09; Japan) | 7.5 |
| 86 | DVD player | 7.5 |
| 87 | Emergency call system control unit | 7.5 |
| 88 | Valid as of 1.6.09 Spare | – |
| 89 | Valid as of 1.6.09: Trailer recognition control unit Valid as of 1.6.09 with engine 156: Oil cooler fan motor relay | 20 |
| 90 | Valid as of 1.6.09 AdBlue® fuse block, AdBlue supply relay | 40 |
| 91 | DC/AC converter control unit | 25 |
| 91 | ECO start/stop: Transmission oil auxiliary pump control unit Valid for engine 642: Vent line heater element | 20 |
| 92 | Valid as of 1.6.09 Spare | – |
| Relay | ||
| A | Terminal 15 relay | |
| B | Circuit 15R relay (1) | |
| C | Heated rear window relay | |
| D | Valid for diesel engine: Fuel pump relay | |
| E | Tailgate windshield wiper relay | |
| F | Seat adjustment relay | |
| G | Circuit 15R relay (2) |
| Fuse Number | Protected Components | Amp. Rating |
|---|---|---|
| 111 | Valid for gasoline engine: ME-SFI [ME] control unit Valid for diesel engine: CDI control unit | 60 |
| 112 | Special-purpose vehicle multifunction control unit | 80 |
| 113 | Valid for engine 156: Left fuel pump control unit, Right fuel pump control unit | 40 |
| 114 | Spare | – |
| 115 | Special-purpose vehicle multifunction control unit | 100 |
Note: Cigar lighter (power outlet) fuses in the Mercedes-Benz C-Class are fuse #9 (Glove compartment power outlet) in the Engine Compartment fuse box, and fuses #71 (Front cigarette lighter, Front interior power outlet), #72 (Cargo area connector box 115 V power outlet), #76 (interior power outlet) in the Luggage compartment fuse box.
Tom Smith is a passionate car mechanic and automotive enthusiast, specializing in the intricate world of car fuse boxes. With years of hands-on experience under the hood, he has earned a reputation as a reliable expert in his field. As the founder and content creator of the popular blog website 'carsfuse.com,' Tom has dedicated himself to sharing his extensive knowledge of car fuse boxes and electrical systems with the world.