Peugeot 206 - Central Door Locking Problem

Fault: Central door locking faults including the Central door locking system not operating on one or more doors and the Central door locking system intermittently locking and then immediately unlocking.
Cause: Repeated problems of Central Door Locking (CDL) failure have been traced to water ingress into the harness plug connection to the CDL unit within the door, causing bad corrosion to the terminals. The central locking motor / switch and lock assembly are all encapsulated within one unit, and individual components cannot be renewed separately. It is not possible to diagnose CDL faults by disconnecting solenoids / switches etc because the Built in Systems Interface (BSI) control module logs a fault. Until the fault is rectified the CDL will unlock instantly.
Rectification: Peugeot recommend replacing both the O/S and N/S CDL units together. The CDL motor / switch assemblies are wired directly to the Built In Systems Interface control module which can be found attached to the interior fuse box situated under the dash on the O/S just above the drivers right knee. New latch assemblies (replacement of both sides is recommended by Peugeot) are supplied with different wiring / harness plug configuration i.e. new latch assemblies have different connecting plug shape / configuration. Therefore the manufacturer includes the new corresponding half of the connecting plug assembly within the replacement parts. To adapt the new latch wiring proceed as follows: Remove existing harness plug from body wiring loom and reconnect to the new replacement harness plug in the following order.

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