A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- A connector or wires under the car: dirt, water or salt after off-road driving
- This unit’s actuator, clutch or sensor
- Low or old oil in the differential or coupling
- The AWD control unit
What you can do yourself
- The clutch won’t disengage, so AWD is engaged all the time. In tight turns on dry tarmac the car may feel like it’s braking, and the tires and clutch wear faster.
- The coupling usually sits by the rear differential under the car: after off-road driving check its connector and wires.
- Fit tires of the same size and wear on all wheels: a mismatch overheats the coupling and differentials.
Stop and don’t drive on if:
- The red brake light is on, or the brake pedal feels soft or sinks
- The steering became very heavy, or the car pulls to one side when braking
OOleg’s tip: check the connector
Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.
Unplug and inspect connectors with the ignition off.
The explanation comes from the error code reference in the AvtoElektrik PRO app.