Error P 0886

I have just picked up our Brabus from the workshop of the Smart Specialists… they don’t know any more:-( He has already been renewed the clutch, the actuator and ECUs. Error message from the N3/10 unit: P886 Relay “K40/1kL” does not switch (Not every time…) Error message from the N15/6 unit: Relay “N10/10k9” does not switch (Always!) When it is parked on R it does not switch to N… and even if it has been parked on N it still doesn’t start. The actuator also makes only easy “Tak Tak”. After 2-3 minutes waiting time (but only when ignition!) it jumps easily and does not cause any problems even during the ride… If you leave the ignition on the fault remains. What can this be?