The symptom is the battery gets drained over and over, and the cause is some stupid motor to close the side door. It thinks the door is not closed, so it keeps trying to close it. The real fix would be to find and realign the door closed sensor, but that is a huge pain, so we just pull fuses and give up using the side door.
The problem here is a 400 mA parasitic drain on the battery. Pulling all fuses in the under hood box gave no relief (though we once mistakenly thought that fuse 15 -- 40A backup/acc fixed things. Disconnecting the alternator did not fix it.
See below -- we ultimately "fixed" this by pulling fuse 7 in the fuse panel inside the vehicle next to the drivers left leg.
I am surprised how many online articles there are about the Odyssey van and parasitic battery drain issues.Search on "honda 40a backup acc drain"
One fellow pulled fuse 26 (front passenger side window switch) and fixed a 320 mA parasitic drain.
I ended up pulling fuse 7 on the drivers side. After I did this, the measured current dropped from 350 mA to 1 mA. With the door open, there was still 250 mA due to the dome light -- so it is important to close the doors then check the current draw.
I never could find a fuse under the hood that I could pull to eliminate the current draw. I don't know the path to get current to that driver side fuse box. I used some wiring diagrams online at Autzone. Even though I looked up the 2006 odyssey, they showed me diagrams for the 2002. Fuse numbers were different and certain fuses that exist in the vehicle were nowhere to be found on the diagrams. They were of little use.
Beyond fuse 7, the likely culprit is the right side sliding door switches -- but I have not made any effort to isolate or check beyond fuse 7. Near as I can tell, it will be "reasonable" to drive the vehicle with fuse 7 pulled.
Tom's Camry pages / tom@mmto.org