2004 Volvo V70 Base, 2.4 61, StandardFACTORY OEM SERVICE PROCEDURE

Tow hitch (optional extra)

Fig 1: Identifying Trailer Module (TRM)
GLL146421Courtesy of VOLVO CARS OF NORTH AMERICA.

The trailer module (TRM) manages the electrical connection between the vehicle and the trailer. The trailer module (TRM) is directly connected to the rear electronic module (REM).

The primary task of the trailer module (TRM) is to manage output signals to the tow hitch cable harness for:

  • Turn signal lamps
  • Brake light
  • Parking lamps
  • Fog lamps.

The rear electronic module (REM) transmits the following voltages to the electrical socket for the tow hitch:

  • Back-up lamp
  • +12V voltage
  • +12V supply.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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