Batteries Dying on New Prism 24G

[falcon50]

I will take it to the Mecedes Dealer, thanks.

[TARVIDSON]

All this may be true but the first thing I would do is stop at a battery store and have them load test the battery. On my 24G the coach battery died after the coach had been at the dealers for an unrelated repair. Whether they did something that destroyed it or it just died I don't know but the battery store solved the question in about 2 minutes. The dealer apparently did not know how to do this. They gave me a new group 27 battery (a bit more capacity)under warranty to replace the original 24 and I purchased another at the battery store as there was plenty of room in the compartment for the two larger batteries. Now we have a lot more capacity.

[falcon50]

Yes, I had planned to do that first but thanks for pointing that out.

[old rv man]

Check all ground connections.my 2015 freelander ground connections were lose.battery dischard,this system is seperate from the truck.I dont think the dealer wants to get into it because it is a rv.

[MarsMan]

My 2015 Prism also did not charge the coach batteries off the MBS Chassis Alternator. Called Coachmen and they said it should and probably a bad fuse or something. I could not figure it out.... took to the place I bought the MH and they spent several hours figuring it out. There is a 1 way diode in the harness coming from the chassis to the coach and the diode was in backwards! they flipped it and now I get 14.2-14.3 V to the coach batteries when the MBS is running. These harnesses come to the factory pre-built...could be the same with yours ?...or not