With a helper on the Use/Store momentary switch, I tested the voltage from the switch yellow wire pair to the converter cabinet latching relay. voltage is 11.5 volts, to each peg depending on the switch position. There is a 1 volt drop from the switch to the latching relay.
I couldn't check the latching relay with the battery charger for some reason, maybe my charger has a built in safety switch wherein it does not close the charging circuit until connected to voltage. Of course the latching relay has no voltage when disconnected. I do have three latching relays which I've swapped around and my thought is not all three are bad.
Stumped.