Re: battery problems
Reply #2 –
Sounds like a bad house battery. Dropping from 13.7 to 12.3 when you turn off the charger is not a good sign. Probably a bad cell. Have them load tested.
The chassis battery dropping from 13.7 to 12.7, particularly if you had any loads on it is not so bad. But, if you have someone load test the house batteries, it would only take another minute to test these as well.
To check the boost switch/solenoid locate the boost solenoid on the front wall of the battery compartment just in front of passengers rear tire. Probably two nuts holding a protective panel over the solenoid. The wiring diagram in your manual will tell you wire numbers that will be attached so you know you have found it.
With shore power/generator off (so charger out of the equation), a bunch of interior lights on (to drop house battery voltage so it is easier to see voltage difference between the two different battery banks and boost switch off, check voltage on both large lugs (house battery is connected to one large lug, chassis to the other). If voltage is the same, remove the small signal wire coming from the dash switch at the solenoid. If you have 12 VDC on that wire, when you remove it, the solenoid should open (and voltage on large lugs be different reflecting voltage of the individual battery banks). This would also indicate that there is a problem with the switch or wiring, because with boost switch off, there should be no voltage to the signal wire.
If no voltage on the signal wire, but voltage is the same on both large lugs, the solenoid has failed in the closed position. Lightly tapping on the solenoid may temporarily free it up, but it needs to be replaced. Be sure to get a CONSTANT DUTY solenoid of the same or greater amperage.
Brett
Topic: battery problems