Well I've trawled the threads, and it looks like I'm stuffed. Was trying to see if there were any loose connections on the AAM to try and solve a central locking problem (can sync up and then lock but nothing else), all the connections were fine, so put it all back together, reconnected the battery and then.......START ERROR.....on the dash. Now apart from crying some more, disconnecting the battery for half an hour, rechecking all the connections on the AAM, checking the battery charge (80%), and still able to do a key sync and lock the doors. I even phone a Merc specialist who said they'd never heard of it! Now reading the threads, I'm supposed to see the red LED blink once when the key is in position 2, it doesn't, on either key (I have two).. So do I really have to open my wallet and say good bye to the contents down at the Mercedes dealer? Oh and I'm in Ireland so the dealers like to double the cost of everything. Any ideas? Its a W163 on a 2000 plate 270CDi Oh and just for fun, after a three hour drive to Galway, all the central locking etc worked fine, for three weeks then back to re-syncing every time I get out of the Car.