cable connections

Sounds like you are correct. Could be that both battery banks are connected together incorrectly, or possibly there is a solenoid that pulls in to connect them together when you push the "AUX" switch on the dash. Sometimes that solenoid gets stuck closed and that will connect both banks together.

larry cad wrote:
Sounds like you are correct. Could be that both battery banks are connected together incorrectly, or possibly there is a solenoid that pulls in to connect them together when you push the "AUX" switch on the dash. Sometimes that solenoid gets stuck closed and that will connect both banks together.

The house batteries were never joined.

There is no solenoid between the house and the chassis. there is no boosted start any longer.
the house batteries are lithium and the chassis are lead acid, this system must have a DC to DC charger separating them.

I simply have the house system on the wrong battery..

Pull the power plug, gen off, disconnect any solar and disconnect all wires from the li negative post. If the house 12V items still work then someone changed the wiring as very unlikely Newmar would wire it that way and a DC clampon meter would be very useful to isolate the problem.

13.4V on the chassis battery doesn't mean it's charged or any good. Load test it. I'd guess it's being charged by the DC DC converter which is inadequate for enought charge in the time frame for a engine start.

CA Traveler wrote:
Pull the power plug, gen off, disconnect any solar and disconnect all wires from the li negative post. If the house 12V items still work then someone changed the wiring as very unlikely Newmar would wire it that way and a DC clampon meter would be very useful to isolate the problem.

13.4V on the chassis battery doesn't mean it's charged or any good. Load test it. I'd guess it's being charged by the DC DC converter which is inadequate for enought charge in the time frame for a engine start.

Chassis batteries were just installed. they hold a charge just fine.
No Solar..
The house system is now working, every light in the coach is on, the furness motor is on, and the microwave is cooking dinner...
the Chassis batteries are holding 13.2 VDC for the past 4 hours.

I think it's fixed.
Thanks for the help.

Ours had a switch to the left of the Driver's seat, if engine or generator wouldn't start flip it and house batteries would send current to starter.
Without examining the situation I can't tell. Call the Factory advisor or tech lines.