Converter mystery

[Johnco]

Here's one for the electrical experts. Early last year I replaced the converter in my 2006 Bambi with Best Converter’s Ultra III converter and 3 stage charger. I monitor my batteries with a Voltminder plugged into the lighter receptacle at the TV. Up to this point when I’m plugged into 110 the Voltminder reads out 13 plus volts (both with the original converter and the new one). This weekend while camping with hook-ups the Voltminder alarm went off and was showing 11.8 volts. I got my tester out and checked the voltage from the converter at the fuse panel and it’s reading 13 plus volts. I checked the batteries and they are barely holding 12 volts, so I guess they are shot, but even if the batteries were gone shouldn't the voltage still be registering higher at the Voltminder while plugged in?

[garry]

Not necessarily, you would think so but corroded connections at the battery or a bad ground connection where the battery attaches to the chassis would cause the battery not to charge and show low voltage at the battery.