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    Fault Codes
    VOLVO
    TRM-8F01
    VOLVO

    TRM-8F01 - Left turn signal lamp. Signal too low

    System

    Trailer Module (TRM)

    Volvo models this fault code applies to

    Applies to the following models:

    3 models

    C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)

    Show models by year and engine (3)
    • Volvo C70 (2006–2013)2006
    • Volvo S40 (2004–2013)2004–2006
    • Volvo V50 (2004–2013)2004–2006

    What does this fault code mean?

    The tow hitch control module (TRM) has registered that the signal for the trailer's left-hand turn indicator is too low in the wire to the trailer socket. The fault lies first and foremost in the wire or the connectors to the socket, where there may be a short to ground.

    Possible causes

    • Short to ground in the signal wire or connectors between the tow hitch control module and the trailer socket

    What you can do

    1. 1Remove any trailer connector from the socket before troubleshooting
    2. 2Use a multimeter to check that the left turn indicator wire has no contact with ground (the body)
    3. 3Check the connectors in the trailer socket for looseness, corrosion and damage
    4. 4Repair the wire or connectors and check that the code does not return

    Symptoms you may notice3

    • The trailer's left-hand turn indicator does not work
    • Information lamp lit
    • Message in the text display

    General guidance for car owners. Diagnosis on the car can point to a different cause.

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