Froelich

I pulled out my BCM to check the model number so I could buy a replacement. Noticed that the circuitry was all nicely potted in what looks like polyamide to protect it from moisture, but it didn’t extend all the way to the edge of the printed circuit board. All along one edge was a white powder that I think was aluminum oxide.
After noting the board numbers I wiped off the powder and put the BCM back. It went from pulling 0.7 amps with the key off to 0.021 amps.
I think the powder was making a resistive leak from the aluminum backing across the insulation layer to the copper circuit layer.
I’m going to pull it back out and clean the edges of the board better and coat them with some clear coat.
just wanted to throw this out there since I see lots of comments about parasitic battery drain.
cheers,
Froelich

Cherryokee

If you plan to "seal" the board edge with clearcoat then you should vacuum-bake the assembly beforehand. This will prevent accidentally trapping moisture within the PCBA when sealed with clearcoat. Another viable solution is to apply a wad of dielectric grease along the exposed area.