VOLVO
REM-1F8C - Trailer foglight driver, signal or temperature too high
System
Rear Electronic Module (REM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The rear electronic module (REM) monitors the power feed to the rear fog lamp through the trailer connector. The code is set when the output is shorted to supply voltage or when the driver stage becomes too hot. The fault can show up as the fog lamp staying on all the time or not working at all.
Possible causes
- Short circuit to supply voltage in the signal wire
- Internal fault in the rear electronic module (REM)
What you can do
- 1Note any other fault codes before clearing the codes, so they can be used in further fault tracing
- 2Check the connectors and wiring in the trailer connector and between the rear electronic module and the trailer module for looseness and corrosion
- 3Switch the rear fog lamp on and off and listen for a click from the relay; a click means the wiring up to the module is probably fine
- 4Use a multimeter to check whether the supply wire to the fog lamp has voltage when the lamp is off; if it does, have a workshop trace the fault further
Symptoms you may notice2
- The rear fog lamp stays on all the time
- The rear fog lamp does not work
What the fault can affect2
- The control module switches off the output to the fog lamp
- On cars built from late September 2005 the output is shut off permanently if the fault has been present over many ignition cycles in a row, until the code is cleared
General guidance for car owners. Diagnosis on the car can point to a different cause.