Reading battery monitor
I have a 2000 Land Yacht XC Diesel Pusher. Four new house batteries and two chassis batteries 18 months old. I have a Ventline Range Hood monitor that is now obsolete. It is 18" long by 3" tall. From left to right there are indicator gauges and lights for H Tank 1, H Tank 2, Fr water, LPG, and Battery 2 Condition and Battery 1 Condition. There is a test button, a W pump button, and Generator start/stop button. The last 4" in the panel are blank. When the test button is pushed the battery indicator lights go from 0-9, 10, 11, 12. Battery 1 condition shows full lights to 12. Battery 2 shows lowest scale at 0-9. Anyone know which batteries are #1 and which are #2? What could be causing Battery 2 indicator light to register lowest at 09? Thanks for any ideas.