This is courtesy of Jerry (halfprice). Thank you Jerry for this Great write up!!!
Quite a while ago i installed a battery disconnect to stop the ghost power draw. I hooked it up the the ground post on the battery closest to the compartment door.
Well ive been having some problems with it. After turning it off the coach still had power. To kill power i had to push the emergency power button on the dash. This button connects the coach and chassis batteries.
I thought the battery isolation manager, BIM, was going bad.
I called bim tech and was told to move the disconnect to the positive post.
There are 4 cables between the 2 batteries. Didnt kbow which cable controlled the coach power. After a call to thor i got the answer. Here it is if anyone needs to know what the cables power.
Rear battery has a cable running to an 100 amp fuse. Its either gen and power jacks or transformer. Second cable goes to 50 amp fuse which runs to the vreaker panel ubder the bed. Front battery has cable to another 100 amp fuse and one to the bim. The last cable is attached to both batteries tying them to each other.
The cable that needs to be disconnected is the 50 amp going to the breakers.
So i swithed the disconnect to this cable and all is well now. No more ghost draw and no need to worry about dead batteries.
I now have a very good ubderstanding what and how the bim works also how to trouble shoot problems with it.
The company was great to deal with and they have a 5 year warranty on the bim.
From what i understand thor switched to the bim a few years ago and they have been working better than the bird.
Jerry used a Marine disconnect switch and rather than using a knife switch for the disconnect I suggest anyone wanting to truly disconnect their batteries pony up and use a Marine disconnect switch, about $20 on Amazon. Better switch, terminals are isolated, and made to use around water.