2004 Mercedes Benz C Class (W203) DirectWire Vehicle Information
All Products
Item Wire Color Polarity Wire Location
12 Volts RED / purple (20A) + Electronic Ignition Switch, plug (C), pin 1
Second 12 Volts red (125A) + driver dash fuse box
Starter purple (for starter kill only) + underhood fuse box, 5 pin plug (C17), pin 1
Second Starter N/A
Ignition pink/red (for ignition sense only) + low curr Electronic Ignition Switch, plug (C), pin 2
Second Ignition N/A
Third Ignition N/A
Accessory N/A
Second Accessory N/A
Third Accessory N/A
Keysense N/A
Data Bus N/A
Can Bus High BROWN / red data CAN distribution connector under driver dash
Can Bus Low brown data CAN distribution connector under driver dash
Can Bus Sw N/A
Power Lock (CAN bus)
Power Unlock (CAN bus)
Lock Motor black 5 wire Left Front Door Module, plug (C4), pin 3
Driver Unlock Motor red 5 wire Left Front Door Module, plug (C4), pin 2
Passenger Unlock Motor red 5 wire Right Front Door Module, plug (C4), pin 2
Parking Lights (-)
Parking Lights (+) gray/black (LF), gray/red (RF) + underhood fuse box, 28 pin plug (C6), pins 2 and 3
The LR - RR wires are gray/black - gray/red at the trunk fuse box, 16 pin plug (C14), pins 6 and 2.
Hazards (CAN bus)
Turn Signal (Left) BLACK/ white (LF) + underhood fuse box, 28 pin plug (C6), pin 8
The LR wire is BLACK/ white at the trunk fuse box, 16 pin plug (C14), pin 9.
Turn Signal (Right) BLACK/ green (RF) + underhood fuse box, 28 pin plug (C6), pin 7
The RR wire is BLACK/ green at the trunk fuse box, 16 pin plug (C14), pin 12.
Headlight yellow/black (L), yellow (R) + underhood fuse box, 6 pin plug (C5), pins 4 and 6
AutoLights
Reverse Light gray/blue + trunk fuse box, 16 pin plug (C14), pin 8
Left Front Door Trigger BROWN / gray - trunk fuse box, 12 pin plug (C2), pin 6
Right Front Door Trigger BROWN / blue - trunk fuse box, 12 pin plug (C2), pin 11
Left Rear Door Trigger BROWN / pink - trunk fuse box, 12 pin plug (C2), pin 10
Right Rear Door Trigger BROWN / white - trunk fuse box, 12 pin plug (C2), pin 12
Dome Supervision (CAN bus)
Trunk/Hatch Pin BROWN / yellow or yellow - trunk fuse box, 28 pin plug (C21), pin 16 or 18
Rear Glass Pin N/A
Hood Pin BROWN / red - hood switch or underhood fuse box, 10 pin plug (C3), pin 7
Trunk/Hatch Release green - trunk fuse box, 28 pin plug (C21), pin 15
Meter this wire while opening the luggage compartment from the handle on the rear of the vehicle.
Trunk Release Motor white 5 wire trunk fuse box, 28 pin plug (C21), pin 21 or 22
Fuel Door Release YELLOW /GREEN or yellow/blue 5 wire trunk fuse box, 4 pin plug (C13), pin 3 or 2
Power Sliding Door (Left) N/A
Power Sliding Door (Right) N/A
Factory Alarm Arm factory remote only
Factory Alarm Disarm factory remote only
Disarm No Unlock
Trunk Alarm Shunt N/A
Tachometer gray/stripe ac any fuel injector
Can also use GREEN/ YELLOW at the underhood fuse box, 28 pin plug (C6), pin 23.
Wait to Start N/A
Neutral Safety N/A
Clutch Pedal brown (in), PURPLE / white or BROWN / pink (out) - N.O. clutch switch, 2 pin plug, pins 1 and 2
Fuel Pump BLACK/ brown or BLACK/ green + trunk fuse box, 7 pin plug (C1), pin 3
Rear Defroster black + latched trunk fuse box, 5 pin plug (C20), pin 5
Mirror Defroster (CAN bus)
Left Front Heated Seat BLACK/ gray 5 wire heated seat switch, plug (C5), pin 2
Right Front Heated Seat BLACK/ purple 5 wire heated seat switch, plug (C5), pin 1
Speed Sense BLACK/ green or BLACK/ gray ac underhood fuse box, 10 pin plug (C7), pin 8 or 10
Brake Wire RED / purple (functions with ignition on only) + brake switch, 4 pin plug, pin 2
Parking Brake BROWN / black - parking brake switch, 2 pin plug, pin 2
Horn Trigger BLACK/ white + underhood fuse box, 10 pin plug (C3), pin 2
Wipers green (L), red (H) + underhood fuse box, 4 pin plug (C16), pins 3 and 4
Left Front Window (Up/Down)
Right Front Window (Up/Down)
Left Rear Window (Up/Down)
Right Rear Window (Up/Down)
Sun Roof (Open/Close)
Sun Roof (Limit/Close)
Memory Seat 1
Memory Seat 2
Memory Seat 3
Radio 12V RED / blue + radio, 8 pin plug, pin 4
Radio Ground brown - radio, 8 pin plug, pin 8
Radio Ignition (CAN bus)
Radio Illumination (CAN bus)
Factory Amp Turn-on blue/black (MOST wake up) radio, 10 pin plug, pin 4 or 18 pin plug, pin 10
Power Antenna black + radio, 8 pin plug, pin 5
Left Front Speaker (+/-) green - BROWN / green +,- radio, 8 pin plug, pins 5 and 6
If equipped, the amplifier is in the right side of the luggage compartment. On vehicles with amplifier, the speaker wires are green - BROWN / green at the amplifier, 26 pin plug, pins 13 and 21.
Right Front Speaker (+/-) orange - BROWN / orange +,- radio, 8 pin plug, pins 3 and 4
If equipped, the amplifier is in the right side of the luggage compartment. On vehicles with amplifier, the speaker wires are orange - BROWN / orange at the amplifier, 26 pin plug, pins 22 and 14.
Left Rear Speaker (+/-) pink - BROWN / pink +,- radio, 8 pin plug, pins 7 and 8
If equipped, the amplifier is in the right side of the luggage compartment. On vehicles with amplifier, the speaker wires are pink - BROWN / pink at the amplifier, 26 pin plug, pins 23 and 15.
Right Rear Speaker (+/-) white - BROWN / white +,- radio, 8 pin plug, pins 1 and 2
If equipped, the amplifier is in the right side of the luggage compartment. On vehicles with amplifier, the speaker wires are white - BROWN / white at the amplifier, 26 pin plug, pins 25 and 17.
Center Channel (+/-) gray - BROWN / gray +,- amplifier, 26 pin plug, pins 16 and 24
If equipped, the amplifier is in the right side of the luggage compartment.
Subwoofer (+/-) paralleled with rear speakers
If equipped, the amplifier is in the right side of the luggage compartment. On vehicles with amplifier, the subwoofer wires are purple - BROWN / purple (1); yellow - BROWN / yellow (2) at the amplifier, 26 pin plug, pins 19 and 11; 20 and 12.
Aux. Audio Input Left (+/-) black - brown +,- radio, 18 pin plug, pins 13 and 5
Aux. Audio Input Right (+/-) yellow - brown +,- radio, 18 pin plug, pins 4 and 5
RSE Video (+/-) N/A
RSE Audio Left (+/-) N/A
RSE Audio Right (+/-) N/A
Satellite Radio 12 Volts RED / black + Satellite Radio Control Unit, 3 pin plug, pin 2
If equipped, the Satellite Radio Control Unit is in the right side of the luggage compartment.
Satellite Radio Ground brown - Satellite Radio Control Unit, 3 pin plug, pin 1
Satellite Radio Ignition blue/black (MOST wake up) Satellite Radio Control Unit, 3 pin plug, pin 3
Satellite Radio Antenna (coaxial cable)
Satellite Audio Left (+/-) (MOST bus)
Satellite Audio Right (+/-) (MOST bus)
Item Size Depth Location
Headunit irregular center of dash
Left Front Speaker 6.5 left front door
Left Front Tweeter left front door
Right Front Speaker 6.5 right front door
Right Front Tweeter right front door
Left Rear Speaker 6.5 left rear door
Left Rear Tweeter left rear door
Right Rear Speaker 6.5 right rear door
Right Rear Tweeter right rear door
Center Channel top center of dash
Subwoofer 9 top center of rear deck
Left Front Headrest
Right Front Headrest
Left Rear Headrest
Right Rear Headrest
Satellite Radio Tuner right side of luggage compartment
Gary Sather