Board work that cures most intermittent faults
Intermittent lock-ups and resets are cured by replacing parts, not adjusting them: new 40-pin connectors between the CPU and driver boards, new sockets in place of the Scanbe ones, a new 1J2 power connector on the CPU board and a new +5 V filter capacitor. While the boards are out, resolder all the .156" male header pins along the board edges, since they crack.
Systems
Related tips
- Slingshot kicker never fires from its switches: loose pin at 2J13
- Freezes mid-game and blows solenoid fuse F2: clean and reseat the 40-pin interconnect
- Damage after the black and white plugs were swapped
- Replace the 40-pin interboard female connector
- Making new interboard male pins long enough
- Removing the old interboard female connector
- Double-solder the CPU board male header pins
- Replace CPU board power connector 1J2
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Three, Clay Harrell (pinrepair.com)