I have a 2004 1.5dci Micra. The rear wiper does not work, the aircon does not operate and when I disconnected the battery earth the car would not start on reconnection. There also seems to be a parasitic drain from the battery. Can I reset the BCM by disconecting the battery terminals and joining the +ve and =ve for 20 minutes to reset the BCM. I understand that early BCM's were fauly prone. Can I upgrade my BCM to a more robust unit. I appreciate this topic might have had a full discussion and if so I would appreciate the link.