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System Overview: Signals

The table below summarizes the input signals to and output signals from the trailer module. The signal types are divided into directly connected signals and CAN communication. The illustration below (Fig 1) displays the same information with the Volvo component designations.

Input signals Output signals
Directly connected:  Directly connected: 
  • Stop lamp signal from right-hand stop lamp (10/43)
  • To tow hitch cable harness:
    • Right turn signal lamp
    • Left turn signal lamp
    • Stop lamp right
    • Stop lamp left
    • Parking lamps
    • Back-up lamp
    • Fog lamps
    • +12 V.
Via Controller Area Network (CAN) communication:  Via Controller Area Network (CAN) communication: 
  • Central electronic module (CEM) (4/56).
  • Central electronic module (CEM) (4/56).
  • Driver information module (DIM) (5/1)
  • Differential electronic module (DEM) (4/82)
  • Parking assistance module.
Fig 1: Identifying Signals
GLL158066Courtesy of VOLVO CARS CORPORATION