CPU connectors that fail most

J1 (5-pin power), J5 (to driver board), J6 (coin door and slam switch) and J7 (playfield switches) are the CPU connectors most often hurt by battery leakage and vibration.

Systems

• Gottlieb System 1

Related tips

• System 1 CPU board connectors
• The CPU to driver board harness
• Which spider chips fail and why
• Aftermarket System 1 CPU boards
• Testing a driver board with a Ni-Wumpf CPU
• Check the TC3 jumper plug on the CPU board
• Replacing the CPU battery with a remote AA pack
• Repairing battery corrosion on the CPU board

Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)