spatjack

Hello, I have a 2006 bmw 525 E60. car came in with a start and stall condition CAS/EWS system checked out ok, after clearing multiple codes 2 kept coming back 2f0d radiator shutter and 2e7c bit serial data. this car is not fitted with shutter control i assume this is an erroneous code. concentrating on 2e7c. unplugged the water pump car starts and runs. plugged a new water pump while engine is running. engine shuts right down. thinking maybe I have 2 water pumps with the same problem connected a blower motor on the water pump circuit runs the motor no problem. intermittently having the alternator plugged in causes the same problem. now I unplug BSD components 1 by 1 clearing each time 2e7c keeps coming back. all BSD's now unplugged still get 2e7c. all body ground connections are ok. positive cable recall was done, checked positive connection at jumper location. anything I'm missing aside from wiring which as far as I can tell is ok. any help in this matterv would be greatly appreciated.
Thank you