Hi all! I've had the unfortunately typical issue of my 2006 R53's sunroof drain line disconnecting above the headliner, which unfortunately got discovered only when coming back from a trip to find a couple inches of water in the driver-side footwell, covering the lower fuses.

I took the time to remove and dry out the carpet but was left several electrical issues (engine starting but not stopping, no tach, etc.). That led me to discovering that the X15 (42-pin) connector under the fuse box was in terrible shape, with several cables breaking off almost immediately.

I opted to splice the bundle of cables leading to the connector, and unfortunately:

1. I wrongfully assumed that the wires would be ambiguous. Turns out there are a couple duplicated colors. There's also more cables on the dash side than the chassis side.

• As such, some cables may be wrongfully spliced - the brown-black pairs, the green+blue pairs, the blue+yellow pairs, one of the two dash-side white+red.
• Lesson learned: I should have taken the time to break the connector housing to be able to do the cables one by one.

2. Probably related: I now have a different set of electrical issues. Things are generally better but:

• My gauges only give readings if I depress the clutch AND hold the ignition in the crank position. Releasing either brings them down to zero. The gauges used to work after the water damage and before my splice job.
• If I connect the brown+black cable leading to the OBD port to the chassis side equivalent, several systems (headlights, climate) stop working, while others (gauge lighting, key sound) start working. I get the same behavior if I connect my OBD-II reader.

At this point... I need help in assessing the problem further. I have a multi

meter and a very basic OBD-II reader... and a lot of perseverance... but not a lot of experience with electrical gremlins. I'm attaching the often-shared pin-out in the image below, which mostly matches my R53. I also attached the 2023 pin-out (PDF file). Thanks all in advance.