Ok I just checked the voltage with the RV plugged in and vehicle off. The voltage is now 12.80V. It seems that the voltage dropped from the previous reading of 13.0V under the same conditions a few hours ago. So does this mean that I should leave it plugged into shore power for a couple of days to recharge that battery until the reading raises to the mid 13 range? By the way is there any danger leaving the RV plugged into shore power charging that battery for a few days. Can the battery get over charged or cause a fire or some other problem? And I'm in Phoenix where the temperature is as hot as hell now. Does that play into the issue at all? Thanks again....Don