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

BL (+) BLU WIRE BLU/WHT WIRE BRN WIRE BRN/RED WIRE BUL (+) CAN HMI H CAN HMI L CAN-B_H STERN CAN-B_L COMPUTER DATA LINES SYSTEM ENGINE COMPARTMENT FUSE, RELAY MODULE FUSE 21 GRY/BLU WIRE GRY/YEL WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED INNER LEFT REAR LAMP UNIT INNER RIGHT REAR LAMP UNIT LEFT REAR LAMP UNIT RED WIRE RIGHT REAR LAMP UNIT SAM CONTROL UNIT (RIGHT FRONT FOOTWELL) VIO/BLK WIRE W/ LED W/O LED

BL/TSI (+) BLK WIRE BLK/RED WIRE BLK/VIO WIRE BLU WIRE BLU/BRN WIRE BRN WIRE BRN/RED WIRE CAN PER H CAN PER L CAN-B_H STERN CAN-B_L CENTER STOP LAMP COMPUTER DATA LINES SYSTEM ENGINE COMPARTMENT FUSE, RELAY MODULE FUSE 21 FUSE 22 FUSE 24 FUSE 48 GRN WIRE GRN/BLU WIRE GRN/VIO WIRE GRN/WHT WIRE GRY/BLU WIRE GRY/BRN WIRE GRY/WHT WIRE HAZARD SIG HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED L/PL/SML (+) DIAG LEFT FRONT LAMP UNIT LEFT LICENSE PLATE LAMP NCA WIRE PNK WIRE PNK/RED WIRE POWER DISTRIBUTION SYSTEM RED WIRE RED/BLK WIRE RED/BLU WIRE RED/YEL WIRE RFL (+) RIGHT FRONT LAMP UNIT RIGHT LICENSE PLATE LAMP SAM CONTROL UNIT (RIGHT FRONT FOOTWELL) SIG SIG (1) SIG (2) SIG 3 TL (+) TL/PL/SML (+) DIAG VIO WIRE VIO/BLK WIRE VIO/GRN WIRE W/ DYNAMIC LED HEADLAMPS W/ STATIC LED HEADLAMPS YEL/WHT WIRE

BLK WIRE BLK/ORG WIRE BLK/RED WIRE BLK/WHT WIRE BLK/YEL WIRE BLU/BRN WIRE BLU/GRN WIRE BRN WIRE BRN/RED WIRE CAN-B_H STERN CAN-B_L CENTER STOP LAMP CLIMATE CONTROL OPERATING UNIT COMPUTER DATA LINES SYSTEM ENGINE COMPARTMENT FUSE, RELAY MODULE FUSE 21 FUSE 24 FUSE 64 GRN WIRE GRN/VIO WIRE GRY/BLK WIRE GRY/BLU WIRE GRY/GRN WIRE HAZARD SIG HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED LEFT FRONT LAMP UNIT LEFT LICENSE PLATE LAMP NCA WIRE PNK WIRE PNK/RED WIRE RED WIRE RED/BLK WIRE RFL (+) RIGHT FRONT LAMP UNIT RIGHT LICENSE PLATE LAMP SAM CONTROL UNIT (RIGHT FRONT FOOTWELL) SIG SIG (+) SIG 1 SIG (1) SIG (2) SIG 3 SML TL (+) TL (+) SIG 1 TL/PL (+) TSI (+) TSI R (+) TSI-L (+) VIO WIRE VIO/BLK WIRE VIO/GRN WIRE

BLK WIRE BLK/YEL WIRE BLU WIRE BLU/BRN WIRE BRN WIRE BRN/RED WIRE CAN B H STERN CAN B L CAN H H CAN H L CAN HMI H CAN HMI L CAN LR H CAN LR L CAN PER H CAN PER L COMPUTER DATA LINES SYSTEM ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FUSE 169 FUSE 22 FUSE 48 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE GRY/BLU WIRE GRY/WHT WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED INSTRUMENT CLUSTER CONTROL UNIT LEFT FRONT LAMP UNIT LIN NCA WIRE PNK WIRE PNK/RED WIRE RAIN/LIGHT SENSOR W/ ADDITIONAL FUNCTIONS REAR AXLE LEVEL SENSOR RED/BLU WIRE RED/WHT WIRE RED/YEL WIRE RIGHT FRONT LAMP UNIT RIGHT FRONT LEVEL SENSOR RIGHT REAR LEVEL SENSOR SAM CONTROL UNIT (RIGHT FRONT FOOTWELL) SIG SIG (1) SIG (2) SIG 3 SIG 4 STEERING COLUMN MODULE CONTROL UNIT VEHICLE INTERIOR FUSE, RELAY MODULE VIO WIRE VIO/WHT WIRE W/ MULTI- LINK AXLE W/ TORSION- BEAM AXLE W/O STEEL SUSPENSION WHT WIRE

BLK WIRE BLK/WHT WIRE BLK/YEL WIRE BLU/BLK WIRE BLU/BRN WIRE BLU/GRN WIRE BRN WIRE BRN/RED WIRE CAN B H STERN CAN B L CAN H H CAN H L CAN HMI H CAN HMI L CAN LR H CAN LR L COMPUTER DATA LINES SYSTEM DTRL ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FUSE 169 FUSE 64 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE GRY/BLU WIRE GRY/ORG WIRE GRY/WHT WIRE HB (+) HB (+) 15 HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED INSTRUMENT CLUSTER CONTROL UNIT LB (+) LEFT FRONT LAMP UNIT LEV (+) LIN NCA WIRE PNK WIRE PNK/RED WIRE RAIN/LIGHT SENSOR W/ ADDITIONAL FUNCTIONS RED/WHT WIRE RIGHT FRONT LAMP UNIT SAM CONTROL UNIT SIG SIG (1) SIG (2) SIG 3 SIG 4 SML STEERING COLUMN MODULE CONTROL UNIT TSI L (+) 31 TSI R (+) TSI R (+) 31 TSI-L (+) VEHICLE INTERIOR FUSE, RELAY MODULE VIO WIRE VIO/WHT WIRE WHT WIRE

BLK WIRE BLK/YEL WIRE BLU/BRN WIRE BRN WIRE BRN/RED WIRE CAN B H STERN CAN B L CAN H H CAN H L CAN HMI H CAN HMI L CAN LR H CAN LR L CAN PER H CAN PER L COMPUTER DATA LINES SYSTEM ELECTRONIC STABILITY PROGRAM CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE EXTERIOR LIGHTS, ELECTRIC PARKING BRAKE SWITCH GROUP FUSE 169 FUSE 22 FUSE 48 GRN WIRE GRN/BLK WIRE GRN/BLU WIRE GRN/WHT WIRE GRN/YEL WIRE GRY/BLU WIRE GRY/WHT WIRE HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED INSTRUMENT CLUSTER CONTROL UNIT LEFT FRONT LAMP UNIT LIN NCA WIRE PNK WIRE PNK/RED WIRE RAIN/LIGHT SENSOR W/ ADDITIONAL FUNCTIONS RED/BLU WIRE RED/WHT WIRE RED/YEL WIRE RIGHT FRONT LAMP UNIT SAM CONTROL UNIT (RIGHT FRONT FOOTWELL) SIG SIG (1) SIG (2) SIG 3 SIG 4 STEERING COLUMN MODULE CONTROL UNIT VEHICLE INTERIOR FUSE, RELAY MODULE VIO WIRE VIO/WHT WIRE WHT WIRE

BRN WIRE BRN/RED WIRE CAN B H CAN B H STERN CAN B L CAN LR H CAN LR L CENTRAL CONTROL MODULE COMPUTER DATA LINES SYSTEM ELECTRONIC IGNITION SWITCH CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE FLEX-E BP PNK FLEX-E BM WIRE FUSE 110 FUSE 21 GRN WIRE HORNS CONTACT PLATE HOT AT ALL TIMES LEFT FANFARE HORN NCA WIRE RED WIRE RED/ORG WIRE RIGHT FANFARE HORN SIG STEERING COLUMN MODULE CONTROL UNIT STEERING WHEEL ELECTRONICS VEHICLE INTERIOR FUSE, RELAY MODULE YEL WIRE YEL/GRY WIRE

ALTERNATOR BATTERY DISCONNECT SWITCH RELAY BATTERY SENSOR BLK WIRE BLU WIRE BRN WIRE CENTRAL CONTROL MODULE DRIVETRAIN CONTROL UNIT DUAL CLUTCH TRANSMISSION FULLY INTEGRATED TRANSMISSION CONTROL ELECTROHYDRAULIC ELECTRICAL POWER STEERING CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE ENGINE COMPARTMENT PREFUSE BOX FAN MOTOR FINE PARTICLE SENSOR FROM ELECTRONIC IGNITION SWITCH CONTROL UNIT (DIAGRAM 7 OF 7) FUSE 1 FUSE 118 FUSE 12 FUSE 14 FUSE 2 FUSE 3 FUSE 40 FUSE 41 FUSE 42 FUSE 43 FUSE 44 FUSE 47 FUSE 48 FUSE 49 FUSE 52 FUSE 53 GRN WIRE LEFT FRONT LAMP UNIT ME-SFI (ME) CONTROL UNIT NCA WIRE ONBOARD ELECTRICAL SYSTEM BATTERY RED WIRE RED/BLK WIRE RED/BLU WIRE RED/GRN WIRE RED/GRY WIRE RED/VIO WIRE RED/WHT WIRE RED/YEL WIRE RIGHT FRONT LAMP UNIT SHORT, LONG-RANGE RADAR SENSOR STARTER, ALTERNATOR CABLE CONNECTOR STATIONARY HEATER UNIT TO BACKUP RELAY (DIAGRAM 2 OF 7) TO VEHICLE INTERIOR FUSE, RELAY MODULE (DIAGRAM 4 OF 7) VOLTAGE DIP LIMITER W/ DYNAMIC LED HEADLAMPS W/ STATIC LED HEADLAMPS WIPER MOTOR

BATTERY SENSOR BATTERY TERMINAL PYROFUSE BLK WIRE BLU WIRE BLU/WHT WIRE BRN WIRE BRN/RED WIRE CAN B H CAN B L CAN C H CAN C L CENTRAL CONTROL MODULE CHARGING CIRCUIT CIRCUIT 50 RELAY COMPUTER DATA LINES COMPUTER DATA LINES SYSTEM ELECTRONIC IGNITION SWITCH CONTROL UNIT ENGINE COMPARTMENT FUSE, RELAY MODULE FLEX-E BM FLEX-E BP FUSE 73 FUSE 75 GRN WIRE GRN/WHT WIRE HOT W/ ENGINE COMPARTMENT TERMINAL 15 RELAY ENERGIZED LIN ME-SFI (ME) CONTROL UNIT NCA WIRE ON-BOARD ELECTRICAL SYSTEM BATTERY ORG/ WIRE PNK WIRE RED WIRE RED/WHT WIRE REL (+) REL GND SIG (1) SIG (2) START/STOP BUTTON STARTER STARTER, ALTERNATOR CABLE CONNECTOR STEERING COLUMN MODULE CONTROL UNIT STERN SYSTEM VIO/WHT WIRE VIO/YEL WIRE VOLTAGE DIP LIMITER WHT WIRE YEL/RED WIRE

BLK/BLU WIRE BLK/YEL WIRE BRN WIRE BRN/GRY WIRE BRN/RED WIRE BRN/YEL WIRE CAN B H CAN B L STERN CAN LR H CAN LR L COMPUTER DATA LINES SYSTEM ENGINE COMPARTMENT FUSE, RELAY MODULE FLUID LEVEL FUSE 169 FUSE 21 FUSE 44 HOT W/ BATTERY DISCONNECT SWITCH RELAY ENERGIZED INDICATOR SWITCH MOT GND/(+) NCA WIRE RAIN/LIGHT SENSOR W/ ADDITIONAL FUNCTIONS RED WIRE RED/BLK WIRE RED/BLU WIRE RED/WHT WIRE SAM CONTROL UNIT SEDAN SIG SIG RBA-2 SPRAY NOZZLE HOSE HEATER (W/ HEATED WINDSHIELD WASHER SYSTEM) STEERING COLUMN MODULE CONTROL UNIT TAILGATE WIPER MOTOR (CENTER OF LIFTGATE) VEHICLE INTERIOR FUSE, RELAY MODULE WINDSHIELD WASHER WINDSHIELD WASHER SYSTEM PUMP WIPER MOTOR