sd2usa2 wrote:
I took the battery out and it started at 12.62 but slowly crept up to 12.7. Something must be short and draining the battery. House batteries were at 12.78 when the chassis battery was hooked in but after 30 min of the chassis battery taken out, it went up to 12.9 at the terminal.
The small voltage increases that you saw are probably just a surface charge and isn't a good indication of the battery condition. A load test is your best tool to get a true indication.
The house voltages reported are very low if the coach is still plugged in and the converter is operational. You should see 13VDC or more with regardless if the batteries in the circuit or not. Try this - unplug the coach, remove a terminals from both the house and chassis batteries and plug the coach back in. Check the voltage between the disconnected terminals. Anything less than 13.2VDC will not keep the house battery fully charged AND the BCC will not tie in the chassis battery to charge it also. The BCC will tie the two together once the voltage exceeds 13.2VDC either from the converter or the alternator.
I'm thinking you might have two problems. Both the chassis battery and the converter are failing.
