2006 9400i with 870 isx.. do data link in dash

[Chamberpains]

When i get a chance later today, I'll see if I can dig up a copy of the schematic for the data link wires. But for now check your firewall connectors. The round 1's on the driver side (turn counter clockwise to remove) and the rectangular 1's on the passenger side (I believe its a 1\4" socket needed to remove them) also as Rawze said remove the ECM connectors and give them a check. they possibly washed dirt or water or even loosened or cut wires at those connectors with their high pressure wand.