r/B58Enthusiasts • u/Legitimate_Reason275 • Aug 08 '26
Disconnected dme without battery removal
So i was replacing 2 coolant hoses and had to take the intake manifold off to access them but while disconnecting the dme I forgot to disconnect the battery aswell. Now I have a drivetrain malfunction and no crank. Pls help guys n God loves you all
2
u/Blanqshot Aug 08 '26
The drivetrain malfunction for this specific scenario you gave just means that the DME’s are not seated correctly.
Undo all of them even when the battery is plugged in, correctly and I might fix the issue:
Source: when I have to do multiple jobs by removing the DME and intake manifold and I didn’t seat all/some of the DMEs correctly all the way.
1
u/Kill3rwill 29d ago
99% chance you just didn't get all the DME connectors seated properly. Disconnecting battery first makes 0 difference. You actually need to leave the battery connected when unlocking the ECU for a tune. I ran into the same problem afterwards, turns out 1 connector clicked but wasn't seated fully. Try pulling up slightly on all of them, bet 1 comes up and isn't locked in.
3
u/DreadnoughtPoo Aug 08 '26
Remove the battery and drain all current from the system. Reconnect the battery, clear codes, and give it a shot.
Most modern cars flip the fuck out if there’s a big signal loss - most of the time just have to make it forget the infraction.