Mercedes-Benz A-class W177 (2018-2023) engine compartment fuse, relay module Wiring diagrams

BLK WIRE BLK/BLU WIRE BLK/RED WIRE BLK/VIO WIRE BLU WIRE BLU/BLK WIRE BLU/BRN WIRE BLU/YEL WIRE BRAKE FLUID LEVEL SWITCH BRN WIRE BRN/BLK WIRE BRN/WHT WIRE BRN/YEL WIRE CAN H H CAN H L CENTRAL CONTROL MODULE COMPUTER DATA LINES SYSTEM ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FLEX-E BM FLEX-E BP FUSE 23 FUSE 24 FUSE 65 FUSE 72 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE GRY WIRE GRY/BLU WIRE GRY/WHT WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED MOT GND/(+) MOT GND/(+) 31 PNK WIRE PNK/GRN WIRE PNK/RED WIRE RED/BLK WIRE RED/BLU WIRE RED/YEL WIRE RIGHT FRONT BRAKE WEAR SENSOR SIG SIG (+) 52 SIG (1) SIG (2) SIG 3 SIG 4 SIG GND VIO WIRE W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED WHT WIRE WHT/YEL WIRE YEL WIRE

BLK WIRE BLK/WHT WIRE BLU WIRE BLU/BRN WIRE BLU/RED WIRE BLU/YEL WIRE BRN WIRE BRN/BLK WIRE BRN/GRN WIRE BRN/RED WIRE BRN/VIO WIRE BRN/WHT WIRE BRN/YEL WIRE CAN B H CAN B H STERN CAN B L CENTER ENGINE HOOD CONTACT SWITCH CENTRAL CONTROL MODULE CENTRAL LOCKING STATUS DISPLAY COMPUTER DATA LINES SYSTEM DCS DCS (+) DCS GND DRIVER DOOR AMBIANCE ILLUMINATION DRIVER DOOR CENTRAL LOCKING INSIDE DOOR HANDLE SWITCH DRIVER DOOR CONTROL UNIT DRIVER DOOR HANDLE AMBIANCE ILLUMINATION DRIVER DOOR HANDLE ILLUMINATION DRIVER DOOR LOCK DRIVER DOOR POCKET LIGHTING ENGINE COMPARTMENT FUSE, RELAY MODULE FUSE 156 FUSE 21 GRN WIRE GRN/BLU WIRE GRN/RED WIRE GRY/RED WIRE HOT AT ALL TIMES LED LIN LOCK UNLOCK MOT GND/(+) MOT- PNK/BLU WIRE PNK/VIO WIRE PNK/WHT WIRE RED WIRE RED/BLK WIRE RED/GRN WIRE SIG SIG (1) SIG (2) SIG GND TRUNK LID/LIFTGATE EXTERNAL OPERATION BUTTON TRUNK LID/LIFTGATE LOCK TRUNK LID/LIFTGATE UNLOCKING BUTTON VEHICLE INTERIOR FUSE, RELAY MODULE VIO/PNK WIRE W/ INCREASED THEFT PROTECTION WHT/GRN WIRE WHT/VIO WIRE YEL WIRE

BLU WIRE BLU/WHT WIRE BRN WIRE CAN HMI H CAN HMI L CAN LR H CAN LR L COMPUTER DATA LINES SYSTEM ELECTRONIC IGNITION SWITCH CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE FLEXRAY E BP PNK FLEXRAY E BM WIRE FUSE 164 FUSE 49 GRN WIRE HOT AT ALL TIMES INSTRUMENT CLUSTER CONTROL UNIT NCA WIRE P NOT RED WIRE RED/GRN WIRE RED/WHT WIRE SIG STEERING COLUMN MODULE CONTROL UNIT STEERING WHEEL DOWNSHIFT BUTTON STEERING WHEEL ELECTRONICS STEERING WHEEL UPSHIFT BUTTON VEHICLE INTERIOR FUSE, RELAY MODULE VIO WIRE VIO/WHT WIRE

58 D AIR CONDITIONING SYSTEM ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/BLU WIRE BLK/ORG WIRE BLK/RED WIRE BLK/WHT WIRE BLK/YEL WIRE BLU WIRE BLU/BLK WIRE BLU/BRN WIRE BLU/GRN WIRE BLU/WHT WIRE BRN WIRE BRN/GRN WIRE BRN/RED WIRE BRN/VIO WIRE BRN/WHT WIRE BRN/YEL WIRE CENTRAL CONTROL MODULE CLUTCH COMPUTER DATA LINES SYSTEM CRUISE CONTROL SYSTEM DOOR LOCKS SYSTEM, ANTI-THEFT SYSTEMS DTRL ENGINE COMPARTMENT FUSE, RELAY MODULE ENGINE CONTROLS SYSTEM FUSE 21 FUSE 40 FUSE 42 FUSE 68 GND KLA GRN WIRE GRN/BLU WIRE GRN/BRN WIRE GRN/VIO WIRE GRN/YEL WIRE GRY WIRE GRY/BLK WIRE GRY/BLU WIRE GRY/GRN WIRE GRY/ORG WIRE GRY/RED WIRE HAZARD SIG HB (+) HEADLIGHTS SYSTEM HEADLIGHTS, EXTERIOR LIGHTS SYSTEMS HORNS SYSTEM HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED HOT W/ ENGINE COMPARTMENT 15 RELAY ENERGIZED HOT W/ TERMINAL ILLU INSTRUMENT CLUSTER SYSTEM LB (+) MOT GND/(+) MOT GND/(+) HAZARD SIG NCA WIRE ORG/ WIRE PNK WIRE PNK/RED WIRE POWER DISTRIBUTION SYSTEM RED WIRE RED/BLU WIRE RED/PNK WIRE RED/VIO WIRE RED/YEL WIRE RELAY ENERGIZED SIG SIG (1) SIG (2) SIG 3 SML STARTING/CHARGING SYSTEM TSI-L (+) TSIR (+) VALVE GND VIO WIRE VIO/BLK WIRE WHT/BLU WIRE WIPER/WASHER SYSTEM YEL WIRE YEL/GRY WIRE

ACTIVE BRAKE ASSIST CONTROLLER UNIT BLK/RED WIRE BRN WIRE CAN HMI H CAN HMI L COMPUTER DATA LINES SYSTEM ENGINE COMPARTMENT FUSE, RELAY MODULE FLEX-E BM FUSE 111 FUSE 70 GRN WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED INSTRUMENT CLUSTER CONTROL UNIT PNK FLEX-E BP WIRE RED WIRE VEHICLE INTERIOR FUSE, RELAY MODULE VIO WIRE VIO/WHT WIRE

BLU WIRE BLU/WHT WIRE BLU/YEL WIRE BRN WIRE CAN C H CAN C L COMPUTER DATA LINES SYSTEM COOLANT TEMPERATURE SENSOR DRIVETRAIN CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE ENGINE COMPARTMENT PREFUSE BOX FAN MOTOR (BEHIND RADIATOR) FUSE 14 FUSE 54 FUSE 71 GRN WIRE GRN/WHT WIRE GRN/YEL WIRE GRY/YEL WIRE HOT AT ALL TIMES HOT W/ HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED ME-SFI (ME) CONTROL UNIT RED WIRE RED/BLU WIRE RELAY ENERGIZED SIG

BLK WIRE BLK/RED WIRE BLK/WHT WIRE BLU WIRE BLU/BLK WIRE BLU/WHT WIRE BRN WIRE CAN H H CAN H L COMPUTER DATA LINES SYSTEM ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE FLEX-E BM FLEX-E BP FLEX-E BP PNK FLEX-E BM WIRE FUSE 107 FUSE 110 FUSE 41 FUSE 47 FUSE 70 GRN WIRE GRN/WHT WIRE GRN/YEL WIRE GRY WIRE GRY/BLU WIRE GRY/WHT WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED INTELLIGENT DRIVE CONTROL UNIT (UNDER FRONT PASSENGER SEAT) ME-SFI (ME) CONTROL UNIT MOT- PNK WIRE RED WIRE RED/GRN WIRE RED/ORG WIRE RED/YEL WIRE SENS (+) SENS GND SENS 1 SENS 2 SIG GND STEERING COLUMN MODULE CONTROL UNIT STOP LAMP SWITCH THROTTLE VALVE ACTUATOR VEHICLE INTERIOR FUSE, RELAY MODULE WHT WIRE YEL WIRE

BLU WIRE BRAKE FLUID LEVEL SWITCH BRN WIRE BRN/GRN WIRE BRN/RED WIRE BRN/WHT WIRE CAN B H CAN B H STERN CAN B L CAN H H CAN H L CENTRAL CONTROL MODULE COMPUTER DATA LINES SYSTEM DCS (+) DCS GND DRIVER DOOR CONTROL UNIT DRIVER DOOR LOCK DRIVER SEAT BELT BUCKLE SWITCH ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FUSE 112 FUSE 156 FUSE 21 FUSE 24 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE GRY/WHT WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED LOCK UNLOCK MOT GND/(+) NCA WIRE OR/GRN WIRE ORG/GRN WIRE PNK/BLU WIRE PNK/VIO WIRE PNK/WHT WIRE RED WIRE RED/BLK WIRE RED/BLU WIRE RED/GRN WIRE RIGHT FRONT BRAKE WEAR SENSOR SIG SIG (1) SIG (2) SIG 3 SIG 4 SUPPLEMENTAL RESTRAINT SYSTEM CONTROL UNIT VEHICLE INTERIOR FUSE, RELAY MODULE W/ INCREASED THEFT PROTECTION WHT WIRE WHT/VIO WIRE YEL WIRE

BRN WIRE BRN/BLK WIRE BRN/YEL WIRE CAN HMI H CAN HMI L COMPUTER DATA LINES SYSTEM ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FLEX-E BP FUSE 24 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE HOT AT ALL TIMES INSTRUMENT CLUSTER CONTROL UNIT LEFT ELECTRIC PARKING BRAKE ACTUATOR MOTOR MOT GND/(+) MOT GND/(+) FLEX E BM PNK WIRE RED WIRE RED/BLK WIRE RED/YEL WIRE RIGHT ELECTRIC PARKING BRAKE ACTUATOR MOTOR SIG (1) SIG (2) SIG 3 SIG 4 VIO WIRE VIO/WHT WIRE

BLU/BRN WIRE BLU/RED WIRE BLU/YEL WIRE BRN WIRE BRN/RED WIRE CAN B H STERN CAN B L CENTRAL CONTROL MODULE COMPUTER DATA LINES SYSTEM DCS ENGINE COMPARTMENT FUSE, RELAY MODULE FUSE 21 GRN/GRY WIRE GRN/WHT WIRE GRY/BLU WIRE GRY/PNK WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED MOT- RED WIRE SIG TANK CAP CENTRAL LOCKING ACTUATOR TRUNK LID/ LIFTGATE LOCK TRUNK LID/LIFTGATE EMERGENCY OPENING BUTTON TRUNK LID/LIFTGATE EXTERNAL OPERATION BUTTON