where is the central locking relay located?
Lock via key fob..OK
Unlock via key fob..NOTOK
I can here a relay switch clicking, but can only gain access via key which opens front doors only.
This doesn't sound like a relay, but more like a latch assembly that is not releasing. The clicking is the attempt of the latch assembly to release itself but it is not successful. You may have a problem with your Body Control Module, which controls the electronic locks, or you may need a replacement latch assembly. Further diagnosis would be possible using a DRB scanner to see if the BCM is storing any codes related to your problem.
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