TRM is the trailer module, one of the 39 modules Ocean Live reads fault codes from with Faults→Scan all modules. The owner guide lists it as TRM (trailer module).
What the app can do
- Read its stored fault codes, and its software version and part number with Faults→Module versions→Read module versions (reading changes nothing).
- Clear codes for this module, only while parked safely. Share the report first: clearing erases the history a workshop would use.
- Ocean Live offers Restart for this module, only while the car is parked safely (see clearing codes and restarting). A restart is not a repair.
Confirmed codes that name it
B20FE16: Trailer module supply voltage below threshold (trailer lamps may not light fully)