Engine batteries discharge sitting

[Jerrydirks]

I have been troubleshooting this problem for some time now. Coach is 2005 Executive pusher. New engine batteries have been installed and tested good. The engine batteries seem to discharge to about 12.5 volts when the MH sits for a day or more. An ammeter on the main lead to the coach shows very low amp draw, .01a. I understand that the engine compartment power panel , Intelletec, connects the coach inverter battery charger when the unit is connected to shore power.

I have looked for a wiring diagram for this power box and inverter wiring to the engine batteries but with no luck. The coach batteries are holding fully charged voltage. Any wiring diagrams and suggestions are very much appreciated!

[vito.a]

I suspect your Big Boy solenoid is not working properly. This is a very common issue. You can replace the Big Boy, or remove it and clean it. Even if you purchase a new one it may only last a few months and it will do the same thing. Some of us think they are using an incorrect dielectric gease and it is burning inside the solenoid.
There is a large copper washer and a contact and they seem to get gunked up from the burned grease. Attached is a guide to rebuilding it courtesy of Mike Canter.
Just be careful working in the rear run bay. There is a lot of current available from those batteries.

[Outbound]

Do you turn off your inverter, battery charger will still work with inverter off.