Its a bit of an odd one. No obvious signs of water ingress but once every couple of weeks it just stops working. Central locking, indicators, heater etc all stop, I can't communicate with it and other modules on the car report no comms with BCM. Disconnect the battery, leave for a about a minute, reconnect and all is ok again for another couple of weeks. Its a bit of a punt going for the BCM but I don't know what else to do with such a intermittent fault! I have advised the customer accordingly of course.