Working on a 98 convertible for a friend. She says it smelled musty when she bought it 3 years ago, and has gotten wet a few times since. Has had a parasitic draw that no one else could diagnose and she was tired of putting batteries in it. After not finding a specialist and the local shops failed to fix it she talked me into looking at it.
When I got there the battery was at 3V and one headlight motor was quietly groaning. She had managed to jump start it once, but had no gauges.
Disconnected headlight, changed battery, added kill switch (knife style).
The car started a few times and had OBDII connection (basic handheld scanner), but when I came back a few days later there was no connection, engine fires but doesn't run. Carpet was wet, so I opened the car to dry out and took the BCM home for a gentle bath. Scrubbed corrosion off and rinsed the board with alcohol.
After reinstall it behaves the same.
I'm about ready to try a passkey relearn, but not sure the security light is functioning to let me know if it's successful. It seems to be always on, even last week when the engine ran.
Fuses are all good, but if you want to suggest a specific one I'll be happy to check again.
Any suggestions on what to try next would be appreciated.
Attached is a picture of the cluster. There is no gauge sweep and the display seems to be nonsense. Also including the corrosion on the BCM that I cleaned with alcohol and soft plastic brush.
Another quirk, there's a irregular clunk in the rear. It sounds a bit like the trunk latch, but more muffled, from somewhere closer to the rear axle, 10 seconds, to 2 minutes apart.