Does anyone have a more detailed wiring diagram of the System 12 Drive than is provided in the print? Or any additional info on it for that matter. I’d like to be able to probe the SCR firing signals with a scope. This is on an ibox controller but I think the drive hasn’t changed that much. The car runs down fine, inspect or auto, but trips on an SCR insufficient armature current fault immediately when trying to run up. I see no voltage at TP3, I’ve swapped the LGA and serial cable as Motion suggested. The SCRs in the direction bridge seem to test good with a meter so I’m thinking the DS card that fires the SCRs.