Does anyone have a very dumbed down drawing of the battery schematic? Both chassis and house. Preferably a 1999 U320...😎. I keep searching and all the tech talk keeps getting really confusing for us non-retired non-electrical engineering types. I mean like really simple. These three little boxes are the chassis batteries, this line is the cable going to... 🙏🏼.
You should have a B-2126 Automotive Wiring Schematic in your owners manual. I know there are a LOT of very tiny little lines on it, but the main battery cable lines are bigger, darker, and pretty easy to follow. You can't make the battery wiring diagram much simpler. It is very helpful to take that page to a local copy store and get it blown up to a larger size. Makes reading/following the lines much easier.
The main advantage to the factory schematic is the lines all have I.D. numbers on them. Compare to the actual cables to help trace the circuits.
If you don't have that schematic, the one linked below should be close for your coach:
https://www.foreforums.com/index.php?action=media;sa=media;in=3297
Easy answer is the red cable should go to the + side marked on the batteries, in this order 123, the negative - side should connect 321