OnCommand reading low voltage

[BoBips]

I have brand new batteries. I’m on shore power. But the OnCommand system says voltage is low, basically constantly. When I start generator, the displayed voltage on the OnCommand screen doesn’t even jump up the voltage like it usually does. It just stays around 11.2 despite batteries being new. Did same with old batteries. any ideas?

[LHaven]

Bad battery ground? Take a voltmeter between the + terminal and frame. If it reads the same as inCommand, take an ohmmeter between the - terminal and frame.

[JRTJH]

New batteries ????

Did you by chance connect them "reversed" ??? Or even accidentally "touched the battery cables to the battery terminals reversed??? If you did, even for a second, the two REVERSE POLARITY fuses on the power panel are blown and it will give you the condition you're experiencing.....

Tere are two styles of converter/charger. One has the reverse polarity fuses located ON THE CONVERTER, the other has them on the face of the fuse panel.
Check the two fuses where ever they are located. Pull them out and either replace with known good fuses or check them with a multimeter.

Your DC distribution panel may not look "exactly like this photo" (50 amp panel vs 30 amp panel) but the reverse polarity fuses will be in a similar location.