Trailer Lamps
System Diagram
| Item | Description |
|---|---|
| 1 | MS-CAN |
| 2 | TRM |
| 3 | Trailer tow connector |
| 4 | HS-CAN1 |
| 5 | BCM |
| 6 | Headlamp switch |
| 7 | Stoplamp switch |
| 8 | GWM |
| 9 | SCCM |
| 10 | LH Steering Column Multifunction Switch |
| 11 | HS-CAN2 |
| 12 | Ignition switch |
| 13 | Start/Stop switch |
| 14 | (without push button start) |
| 15 | (with push button start) |
Network Message Chart
GWM Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Parklamp status | BCM | A command to activate/deactivate the park lamps output. |
| Turn signal switch status | SCCM | Indicates the turn signal stalk position on the LH steering column multifunction switch (left/right lane change or turn signal on or off). |
| Turn indication request | BCM | A command to activate/deactivate the exterior mirror turn indicator. |
| Stoplamp brake request | BCM | A command to activate/deactivate the stop lamps output. |
TRM Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Turn indication request | BCM | A command to the TRM to activate/deactivate the turn indicator output to the trailer tow connector. |
| Stoplamp request | BCM | A command to the TRM to activate/deactivate the stop lamps output to the trailer tow connector. |
| Parklamp status | GWM | A command to the TRM to activate/deactivate the park lamps output to the trailer tow connector. |
Trailer Stop-Turn Lamps
The SCCM monitors the LH multifunction switch position. When the LH multifunction switch is in the left or right turn position, the SCCM sends a message over the HS-CAN2 to the GWM then the GWM sends the message to the BCM over the HS-CAN1 indicating a request for the LH or RH turn signal.
When the BCM receives a request for a turn signal, the BCM sends a turn indicator command message over the MS-CAN to the TRM to activate the requested turn indicator output to the trailer tow connector.
When the BCM receives input from the stoplamp switch indicating that the brake pedal is being pressed, the TRM receives a stoplamp activation message over the MS-CAN.
Trailer Parking Lamps
The BCM monitors the headlamp switch position by sending voltage signals on multiple circuits to the headlamp switch. There is one circuit for each headlamp switch position. At any given time, one of the signal circuits is switched to ground to indicate the headlamp switch position.
When the parking lamps or headlamps position is selected, the BCM sends a position light indication message over the MS-CAN to the TRM to activate the parking lamps output to the trailer tow connector.