Forgive as this is long - but I wanted to give the details.  We are having an issue with the batteries charging.  I have a 2010 Fiesta 34B, purchased used last year, been working fine through the summer trips.  Keep it attached to shore power with A/C in operation.  Two weeks ago I noticed the A/C short cycling (about 30-60 seconds).  Went inside to find dashboard radio flickering, all 12 volt lights were dim, etc.  Immediately though the the converter/charger was not working.  Opened the area behind the power center to access the converter.  It was difficult to tell if it was functioning.  I check the output with the multi-meter and the voltage was fluctuating all over the place.  I checked the cost and ordered one to be delivered that Sunday.  I immediately dug out the other chargers to see if I could bring the batteries back up.  I left those chargers in place for the week and they appeared to recharge fully.  I replaced the charger with the new one and hooked everything back up and removed the external chargers.  I also checked every in-line fuse to make sure it was still good - no issues there.  I left everything off for a few hours and checked the readout on the dash.  They were at 13.68 and 13.56 about 4 hours later.  I turned the refrigerator on and let it sit overnight.  Yesterday afternoon the voltage was still hanging close to the 13.6, 13.5 range.  This afternoon I checked the voltage and both are down to the 13.1 range.  While I realize the resting voltage of a 12-volt is lower than this I don't recall it dropping off this much previously while being plugged in.  Am I right in thinking something is still wrong?  If so, any idea where to turn next?  Is there some fuse I haven't though of?  I appreciate any assistance you can provide. Thanks