Mercedes W169 represents the second generation of the A-class Mercedes-Benz which was produced in 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 and was designated as Mercedes A150, Mercedes A160, Mercedes A170. During this time, the model was restyled. In this material you will find information about the location of all electronic control units, a description of fuses and relays Mercedes w169 with block diagrams and photo examples of their implementation. Note the cigarette lighter fuse.
The design of the blocks and the arrangement of the elements in them may differ from that provided and depends on the year of manufacture and the level of electrical equipment of your car.
Location
General layout of control units
Description
| 1 | Electronic control unit ABS |
| 2 | Air conditioner control unit – in the heater control panel |
| 3 | Antenna Signal Booster 1 |
| 4 | Antenna Signal Booster 2 |
| 5 | Side impact sensor (left) |
| 6 | Side impact sensor (right) |
| 7 | Anti-theft system control unit |
| 8 | Vehicle tilt sensor (anti-theft system) |
| 9 | Anti-theft alarm sound signal – on the intake system resonator |
| 10 | Volume change sensors (anti-theft system) |
| 11 | Audio system |
| 12 | Additional heater |
| 13 | Battery |
| 14 | CAN data bus, gateway control unit |
| 15 | Central lock signal sensor (infrared) – in the driver’s door handle |
| 16 | Diagnostic Link Connector (DLC) |
| 17 | Left front door electrical control unit |
| 18 | Left rear door electrical control unit |
| 19 | Right front door electrical control unit |
| 20 | Right rear door electrical control unit |
| 21 | Fuse/Relay Box Instrument Panel |
| 22 | Fuse/Relay Box, Footwell |
| 23 | Sound signals – behind the front bumper |
| 24 | Ignition switch control unit |
| 25 | Electronic immobilizer control unit – (combined with ignition switch control unit) |
| 26 | Ring antenna of the immobilizer |
| 27 | Direction indicator/hazard warning relay – in multifunction control unit |
| 28 | Lighting control unit |
| 29 | Multifunction control unit – connected to footwell fuse/relay box – functions: Interior lights, exterior lights, horns, windscreen wipers, central locking, electric windows, direction indicators, anti-theft alarm, sunroof, seat heaters, immobiliser |
| 30 | Multifunctional steering wheel controls |
| 31 | Multifunction switch control unit |
| 32 | Navigation system control unit |
| 33 | Ambient air temperature sensor |
| 34 | Parking system control unit |
| 35 | Power Steering Control Unit |
| 36 | Rain sensor – in the interior rearview mirror |
| 37 | Seat heating control unit |
| 38 | Passenger presence sensor on the seat – in the passenger seat |
| 39 | Steering column electrical equipment control unit |
| 40 | SRS Electronic Control Unit |
| 41 | Telephone Network Connection Module |
| 42 | Phone Interface Control Unit |
| 43 | Trailer electrical equipment control unit |
| 44 | Electronic control unit of the gearbox – in the gearbox |
| 45 | Windshield wiper intermittent relay |
Fuse box
The main fuse box is located next to the battery in the front passenger footwell and can be accessed by removing the floor trim.
Designation
| F1 | 10A Pre-styling: Brake light switch |
| 5A Facelift and pre-facelift with code U58 (exterior lighting package): Brake light switch | |
| F2 | 25A Rear window heating |
| F3 | 7.5A Instrument cluster |
| EZS control unit | |
| F4 | 15A EZS Control Unit |
| Electric steering lock control unit | |
| F5 | 7.5A HAU Control Panel |
| KLA control panel (automatic air conditioning) | |
| F6 | 15A Left horn |
| Right horn | |
| F7 | 25A Fuel pump with fuel level sensor |
| F8 | 25A Ceiling Control Panel |
| F9 | 40A ESP and BAS control unit |
| F10 | 40A Fan Motor |
| F11 | 30A Motors 266: Terminal 87 Electrical Circuit Relay, Motor |
| 40A Motors 640: Terminal 87 Electrical Circuit Relay, Motor | |
| F12 | 5A Electronic Steering Column Module |
| Multifunctional steering wheel | |
| F13 | 25A Front Left Door Control Unit |
| F14 | 25A Front Right Door Control Unit |
| F15 | 25A ESP and BAS control unit |
| F16 | 10A Diagnostic socket |
| PTS control unit (parking sensors, dorestyling) | |
| F17 | 5A Outdoor Lighting Rotary Switch |
| F18 | 7.5A Gearbox 711, 716: Reverse Light Switch |
| F19 | 5A Micromechanical Angular Rate Sensor AY |
| F20 | 7.5A Passive safety system control unit |
| F21 | 30A Starter |
| F22 | 7.5A Instrument cluster |
| F23 | 20A Engines 640 (from 1.9.08): Fuel filter condensate sensor with heating element |
| 7.5A Pre-styling: Heated washer nozzles | |
| F24 | 7.5A Electric Power Steering (ES) Control Unit |
| F25 | 7.5A Brake Light Switch |
| ESP and BAS control unit | |
| F26 | 7.5A Gearbox 722: Electronic Selector Lever Module Control Unit |
| F27 | 10A Transmission 722: Electrical Control Module CVT (Continuously Variable Automatic Transmission) |
| F28 | 5A Outdoor Lighting Rotary Switch |
| F29 | 30A SAM Control Unit |
| F30 | 25A Relay electrical circuit terminals 87F |
| F31 | 5A Outdoor Lighting Rotary Switch |
| Central interface control unit (vehicles up to 11/30/05) | |
| F32 | 7.5A Engines 266: Control Unit ME |
| F33 | 15A Audio system |
| Audio module and navigation unit | |
| Control and indication panel COMAND | |
| F34 | 25A Rear Left Door Control Unit |
| F35 | 25A Rear Right Door Control Unit |
| F36 | 10A Restyling: PTS control unit (parking sensors) |
| Trailer control unit | |
| 7.5A Pre-styling: Trailer control unit | |
| Mobile phone electrical circuit connector | |
| F37 | 7.5A Passive safety system control unit |
| Front passenger seat occupant/child seat recognition sensor | |
| Front passenger seat occupancy recognition system | |
| F38 | 25A Cigarette Lighter with Illuminator, Front |
| F39 | 25A Windscreen Wiper Motor |
| F40 | 25A Sectional Roof: Overhead Control Panel (Sunroof Motor) |
| 7.5A Ceiling Control Panel | |
| F41 | 15A Tailgate Wiper Motor |
| F42 | 7.5A Glove box light with micro switch |
| Vanity mirror lighting left and right | |
| Pedal Pressure Monitoring Sensor (Driving School Package) | |
| Footwell Light Switch (Driving School Package) | |
| VICS+ETC Power Supply Plug-in Connection (Japan) | |
| Emergency Call System Control Unit (USA) | |
| F43 | 7.5A Motors 266: Cable Lug Electrical Circuit Terminals 87M1e |
| 15A Motors 640: Cable Lug Electrical Circuit Terminals 87M1e | |
| Dual Fuel Gas Petrol Engine: Electrical Circuit Terminal Cable Lug 87M1e | |
| F44 | 15A Motors 266: Cable Lug Electrical Circuit Terminals 87M2e |
| 20A Motors 640: Cable Lug Electrical Circuit Terminals 87M2e | |
| F45 | 25A Engines 640: CDI Control Unit |
| F46 | 25A Woofer (Japan, restyling) |
| 40A Speaker Amplifier (restyling) | |
| 7.5A UHI (Universal Mobile Interface) Control Unit (pre-restyling) | |
| GSM 1800 network compensator (pre-styling) | |
| Phone control unit (Japan, pre-styling) | |
| F47 | 7.5A Mobile Phone Electrical Circuit Socket |
| UHI (Universal Hi-Fi Interface) Control Unit | |
| Voice control system control unit (pre-restyling) | |
| Phone control unit (Japan, pre-styling) | |
| F48 | 7.5A EDW/Towaway Protection/Interior Protection Control Unit |
| Alarm siren | |
| F49 | 25A Upper Control Panel |
| Heating element of the front left seat cushion (pre-restyling) | |
| Heating element of the back of the front left seat (pre-restyling) | |
| Heating element of the front right seat cushion (pre-restyling) | |
| Heating element of the back of the front right seat (pre-restyling) | |
| F50 | 7.5A Multimedia Interface Control Unit (restyling) |
| Digital TV tuner (restyling) | |
| Control unit of the digital audio broadcasting system (restyling) | |
| CD changer (pre-restyling) | |
| Plug-in connection VICS+ETC power supply (Japan, pre-styling) | |
| 30A Company Vehicles: Roof Bar | |
| Cable lug electrical circuit terminals 30 | |
| F51 | 10A Weight Sensing System (WSS) Control Unit (Canada) |
| Control panel for the special signaling system (official vehicles) | |
| F52 | 7.5A Emergency call system control unit (vehicles up to 31.5.06) |
| 5A VICS+ETC Power Supply Connector (Japan, vehicles up to 31.5.06) | |
| F53 | 30A Interior Socket |
| Cigar lighter with illuminated ashtray, rear | |
| F54 | 15A Service vehicles: Socket 2-pole 12V |
| 25A Speaker Amplifier (pre-restyling) | |
| Low frequency speaker (pre-restyling) | |
| F55 | 7.5A Pre-styling and restyling with code 614: |
| Front left headlight | |
| Front right headlight | |
| 10A Restyling: Front left headlight | |
| F56 | 10A Restyling: Front right headlight |
| F57 | 15A AHV towing hitch connector, 13-pin (restyling) |
| 20A Audio Interface Control Unit (Japan. pre-restyling) | |
| 7.5A Emergency Call System Control Unit | |
| SDAR control unit | |
| F58 | 25A Trailer Control Unit |
| F59 | 20A AHV Towbar Plug, 13-Pin |
| Trailer control unit (vehicles up to 31.5.05) | |
| F60 | 20A Driver Seat Contact Strip |
| F61 | 20A Front Passenger Seat Contact Strip |
| F62 | 40A Restyling: Terminal 15 (2) electrical circuit relay (additional equipment: xenon headlights, mobile phone) |
| 25A Pre-styling: Relay of the electric circuit of terminal 15 (2) (additional equipment: xenon headlights, mobile phone) | |
| F63 | 7.5A SDAR Control Unit (Canada) |
| 25A Roof Bar (Office Vehicles) | |
| F64 | 40A Engines 266: Air Pump Relay |
| 80A Engines 640: Glow Plug Time End | |
| F65 | 80A Electric Power Steering (ES) Control Unit |
| F66 | 60A SAM Control Unit |
| F67 | 50A Terminal 15R (2) Electrical Circuit Relay (Optional) |
| F68 | 50A Standard equipment (facelift): Electric intake fan for engine and air conditioner with integrated regulator (Pre-facelift: (valid for engine 266.920 and 266.940 with gearbox 722)) |
| 60A Special equipment (facelift): Pre-facelift: (valid for engines 640.940, 640.941, 266.960, 266.980 and for engines 266.920, 266.940 with code (550): Towing hitch)) | |
| F69 | 50A Electrical Circuit Relay Terminal 15R (1) |
| F70 | 60A Electrical Circuit Relay Terminal 15 (1) |
| F71 | 150A 640 Motors: PTC Auxiliary Heater |
| F72 | 60A Pre-styling: Cable lug electrical circuit terminals 30 |
| Official vehicles: | |
| Fuse 7 (F7f7) | |
| Fuse 10 (F7f10) | |
| Taxi: | |
| Multifunctional control unit of special vehicle (MSS) |
Fuses 38 and 53 are responsible for the operation of the cigarette lighters.
Relay block
Under the dashboard, at the front passenger’s feet, there is a block with a relay. To access it, you need to remove the interior trim. You don’t need to remove the glove compartment.
Purpose
| Fuses | |
| 80 | 30A Taxi, Service, Rental Cars: Multifunctional Special Vehicle Control Unit (MSS) |
| 81 | 30A Taxi, Service, Rental Cars: Multifunctional Special Vehicle Control Unit (MSS) |
| 82 | 30A Taxi, Service, Rental Cars: Multifunctional Special Vehicle Control Unit (MSS) |
| 83 | 30A Taxi, Service, Rental Cars: Multifunctional Special Vehicle Control Unit (MSS) |
| Relay | |
| A | Relay electric circuit terminals 15R (2) |
| B | Relay electric circuit terminals 15R (1) |
| C | Sound signal relay |
| D | Rear window heating relay |
| E | Windscreen wiper relay, mode 1/2 |
| F | Windscreen Wiper Relay ON/OFF |
| G | Relay electric circuit terminals 15 (1) |
| H | Backup relay |
| I | Air pump relay |
| K | Fuel pump relay |
| L | Relay el. circuit terminal 87, engine |
| M | Starter relay |
| N | Relay el. circuit terminals 87F |
| P | Relay electric circuit terminals 15 (2) |