Re: New to SMB, mostly electrical, some layout
Original batteries on a 13yr old van are most likely toast, even if they were lovingly cared for, both starting and house.
I've got an '02 7.3 and my second starting battery in on the rail just behind the wheel well on the passenger side.
My house batteries are under the floor near the smaller side barn door. I access them through a trap door under the rug just inside the barn door but I think the vans PO made that mod. I use 6V liquid acid golf cart batteries that need attention about every 90 days so the trap door is practically necessary.
2002 E350 7.3 PSD
Quigley 4x4, EB50 floorplan