I just purchased a 2003 Airstream Land Yacht 36 XC Motor Home with Cat 300 diesel engine. On our way home from Parkersburg WV about an hour into the trip, the battery light on dash came on. It was getting dark but I turned off headlights and limped on until I finally had to turn headlights back on. The coach didn't die and actually the lights did not seem to get any more dim the further we drove (two more hours to north central Ohio)
I got home and plugged it into shore power and the Progressive Industries Power Management system shows pulling about 30 amps initially from 110 shore power during bulk charge and over a few hours eventually goes to float charge and only pulling an amp or less.
I took two more short trips here in town with total running time about an hour each time and both times when I return home and plug into shore power, same story pulling lots of current to bring batteries up.
Airstream tech manual says shore power network charges both coach batteries (four) and chassis batteries (two). Four coach batteries are hooked in parellel and two chassis batteries also hooked in parellel. They are ALL flooded lead acid type. How can I figure out which battery is causing the problem? Or how can I determine if it is any of the batteries or is it the chassis alternator? It seems to me that if I have them all topped off via shore power and then take a short drive of an hour or so and do not use any 12 COACH systems and the dashboard battery light comes on, it's very likely a chassis battery or alternator. I wouldn't think the COACH batteries would draw down with very little or no load on them, i am not running the fridge, water heater, furnace or any other 12 volt
Any insight you can give me on how to trouble shoot this is appreciated. By the way, all six batteries are the same model number. Shouldn't the chassis batts be for high cranking amps and the coach batts be for deep cycle? How do I tell them apart? (That's a question for the manufacturer) Did the previous owner buy the wrong batteries? By the way - anybody have any idea what the on off switch is for in the picture? (next to the genset hour meter)