fuse 21...

[steelynorm]

having issues with parasitic drain..
narrowed it down to fuse 21...
yanked fuse today... and noticed while driving my obc would occasionaly power on for brief moment.. like less than a second..

??? short maybe?
it it only powered on intermittently could that draw my battery down..

[spdracrm3]

year and model?
just randomly pulled up a 87 325i ETM and there are a lot of things on that 21 fuse such that you will probably have to start dis-connecting them all to narrow it down....(how many milliamp draw?)
as far as the OBC there are 4 other fuses feeding that so entirely possible that it powers up randomly ,i would start by disconnecting it first as it acting weird already

[RobDog]

I have had this problem twice before with fuse 21. The 1st time was the si board lights staying on with the car off (failed si board). The 2nd time was my trunk light staying on (trunk out of adjustment, also the cause of the rattle when I drove over bumps).