Trying to rehab a Gottlieb system 1 Pinball Pool. Was checking the voltages and the 6V DC voltage was 15V. I figured it was the bridge rectifier and replaced. Same voltage after replaced when rectifier was fully connected. When I remove the + lead, voltage drops to 12V. When I remove both the ground and positive DC lead, the voltage drops into the 7 volt range which is acceptable. Reconnect the ground only and jumps back up to 12V. Any suggestions?
Couple of points: This is with all boards unplugged. The rectifier worked fine tested out of the pinball machine. Just going through the power bottom board right now to confirm voltages. Just received a PI-1x4 board from Pascal Janin and wanted to check voltages before connecting the new board. This is my first rehab.