Thanks for the heads up, have not looked at that, do not have any aftermarket alarms etc. Have read that a 3 series owner hadsame problem and was issues with pins on a connector in the door itself, either corrision or wires breaking with age. Have been swapping components out with another car the same but no luck to date. Other ideas have been bad ground connection or intermitent power failure, relay? Will keep trying, has happened 3 times over 400k of driving at seeming completely random times.