VIN inconsistency
The DCU must be programmed for the vehicle and the particular door where it is installed (can be done with SDP3).
What you'll see
The door may have function degradations, move too slow or fast, or even not function at all. But if the DCU happens to have a suitable parameter setting in memory it may show no symptoms and appear to work normally.
System reaction
The DCU signals 'Major fault' over CAN to MBS, which then requests 'Door malfunction' notification and an exclamation mark indication in the related door in Bus stop page in ICL.
Diagnostic depth
The DCU has detected a mismatch between the chassis number in its memory and the chassis number of the vehicle.
-The DCU has no chassis number (it has never been EOL programmed). -The DCU has been installed in a vehicle for which it was not EOL programmed. -A programming of the DCU has failed.