I have MRL 3300 going down on 74 thought this was created from customer from powering down batteries measure 12.7 and 25.4 in series. shouldn't this be enough? After clearing faults and soft reset still getting 74 control state .
That sounds like a bad test to me. Batteries are checked (properly) under load. Disconnect them and check them with a load tester It's the only way to accurately test batteries. What you use for load can vary, but I get the best and easiest results from one of these.
A good 12v 7.5ah battery will go to 9 volts and hold steady there. A bad one will start at less than 9 and go down or instantly drop to zero. For reference.
Thank for the info so we replaced batteries powered up got car back running ,ran for good while then fault came back first 74 status and then the 0063 fault looking further the wires on the AC/DC connector looks somewhat suspect so removed connector remove wires and reconnect seemed problem went away they have #14 wire being used thought that's was possible issue returned to service ran for maybe a day then shutdown again same fault reset car looking at the board wiggle connector and relays chatter on same board think it's called Sema board gonna replace that board and maybe the connector so we'll see.
