Engine start-up failure in BMW models

Today we will describe a failure that affects the X6 35 xdrive aut. E71 (30 6D 5) model of the BMW brand, specifically a failure related to the engine.  

AFFECTED VEHICLE

BMW X6 35 xdrive aut. E71 (30 6D 5)

SYMPTOM

The engine does not start.

FAILURES REPORTED

Failures codes reported by the DDE engine control unit.
 

507D – Parking lock deactivated erroneously.

CF37 – CAS messages in the wrong K bus.

CAUSE

If the engine fails to start, due to a voltage drop caused by an excessive requirement when starting the engine, either because of a low battery or because of keeping the ignition switched on over an extended period of time, this may be due to a lack of communication between the CAS (Car Access System) unit and the DDE (Digital Diesel Electronics) engine control unit.

NOTE: It should be noted that in this model, in case of a real problem with the CAS (Car Access System), the starter motor is not launched.

REMEDY

Pairing of the CAS and DDE units with an appropriate diagnostic tool.