MCU_R is the rear motor module, one of the 39 modules Ocean Live reads fault codes from with Faults→Scan all modules. The owner guide lists it as MCU_F / MCU_R (front / rear motor).
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 never offers Restart for this module, whatever state the car is in: it is one of the brakes, steering, airbags, drive, gateway or high-voltage battery modules. Clearing its codes is still possible.
Airbag (ACU), brake (ESP, IBOOSTER), steering (EPS) and high-voltage (BMS, PDU, PIU, MCU) faults should go to a qualified shop.