Range Rover (LM) V8-4398cc 4.4L (M62) (2003)
Trailer Connector: Description and Operation
TRAILER SOCKET
DESCRIPTION
General
The trailer socket is mounted at the rear of the vehicle, and receives inputs from the trailer ECU. The trailer ECU is mounted behind the rear fuse box, on
the RH side of the luggage compartment. The trailer ECU receives inputs from the Light Check Module (LCM), which is located at the base of the RH
'A' post.
OPERATION
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fusible link 5 and fuse 53 of the passenger compartment fuse box (C0632) on an R wire.
Fusible link 5 (C0588) is connected to fuse 4, fuse 6, and fuse 17 of the rear fuse box (C2024) by an R wire. Fuse 4 and fuse 6 (C2020) supply constant
battery feeds to the trailer socket (C0499) on RY and RU wires respectively. Fuse 17 (C2022) provides a constant battery feed to the trailer ECU
(C0380) on an RW wire.
Fuse 53 of the passenger compartment fuse box (C0583) provides a constant battery feed to the ignition switch (C0028 on V8 vehicles) on an R wire.
When the ignition switch is turned to the 'auxiliary' position, current flows across the switch (C0028 on V8 vehicles) to fuse 2 of the passenger
compartment fuse box (C0585) on a G wire. Fuse 2 (C0587) provides an auxiliary ignition feed to the trailer socket (C0499) via the rear fuse box
(C2022) on a GY wire.
Light Check Module (LCM)
The LCM provides signal inputs to the trailer ECU as follows:
Rear Fog Lamp
The rear fog lamp function of the trailer ECU is controlled via a bi-directional data line between the LCM (C2040) and the trailer ECU (C0380) on a
UNY wire. When the trailer ECU receives a rear fog lamp signal, it provides a feed to the trailer socket (C0409) on a YR wire.
Reverse Lamp
The reverse lamp function of the trailer ECU is controlled via a bi-directional data line between the LCM (C2040) and the trailer ECU (C0380) on a
UNY wire. When the trailer ECU receives a reverse lamp signal, it provides a feed to the trailer socket (C0499) on a YU wire.
RH Tail Lamp
When the LCM (C0937) detects that side or headlamps have been selected, it provides a feed to the trailer ECU (C0380) on an SP wire. The trailer ECU
(C0380) will now provide a feed to the trailer socket (C0499) on an SR wire.
LH Tail Lamp
When the LCM (C2040) detects that side or headlamps have been selected, it provides a feed to the trailer ECU (C0380) on an SW wire. The trailer
ECU (C0380) will now provide a feed to the trailer socket (C0499) on an SB wire.
RH Direction indicator Lamp
When the LCM (C2039) detects that a right turn has been selected, it provides a feed to the trailer ECU (C0380) on a UN wire. The trailer ECU (C0380)
will now provide a feed to the trailer socket (C0499) on a UY wire.
LH Direction Indicator Lamp
When the LCM (C0937) detects that a left turn has been selected, it provides a feed to the trailer ECU (C0380) on a UG wire. The trailer ECU (C0380)
will now provide a feed to the trailer socket (C0499) on a UR wire.
Brake Lamps
When the LCM (C0937) detects that the brake pedal has been pressed, it provides a feed to the trailer ECU (C0380) on a BU wire. The trailer ECU
(C0380) will now provide a feed to the trailer socket (C0499) on a BW wire.