I like DOWNTHEROADs theory. You need to measure the DC VOLTAGE of the batteries at the battery terminals when the converter is turned OFF.
Use this CHART to determine the approximate state of charge of the battery.
It could a battery cell has boiled-out its fluids and now failed. The converter is trying to get the battery back up to its full charge state and will constantly be working hard to do this...
If the battery is reading below the 50% charge state and cannot be brought back to normal full charged state then internal destruction is probably already started and a new battery may need to be purchased.
The converter will normally put out 13.6VDC to charge the battery. If the converter is using smart-mode charging technology then you may see as high as 14.4VDC feeding the battery.
If the battery has a boiled-out cell then it will draw alot of current from the converter when being charged and will eventually blow fuses or make the converter go bad as well...
Having a multimeter around is almost a must have test meter when working working with converters and batteries.
This is what an inexpensive multimeter looks like...
Knowing the model number of the converter/charger unit would be useful information as well.
just some of my thoughts here...
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
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