VOLVO
TRM-8C01 - Fog lamps. Signal too low
System
Trailer Module (TRM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (3)
What does this fault code mean?
The tow hitch control module (TRM) has registered that the signal for the trailer fog lamps 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
- 1Remove any trailer connector from the socket before troubleshooting
- 2Use a multimeter to check that the fog lamp wire has no contact with ground (the body)
- 3Check the connectors in the trailer socket for looseness, corrosion and damage
- 4Repair the wire or connectors and check that the code does not return
Symptoms you may notice3
- The trailer fog lamps do 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.