306 central locking

Hi people I have a problem with the central locking on 1996 306 diesel, the indicators have stopped flashing when the deadlocks are engaged, when doors are unlocked ALL of the indicators flash when either left or right is used.every thing else works as normal I suspect the cental locking relay is the culprit.If anyone has a different view I would love to hear from them. Also where is the relay it sounds like it could be in the drivers door??? Tia Al