A circuit routed through the auxiliary power driver board has no power although its fuse and parts test good.
Circuit dead through the auxiliary power driver board: open zero-ohm jumpers
Cause: Zero-ohm resistors used as jumpers on this board can fail open.
Checks
- With the game off, measure continuity across jumpers W1, W3, W4 and W6 on the board.
Fix
- Replace any open zero-ohm jumper with a plain wire jumper.
Systems
Related tips
- What the System 11 auxiliary power driver board does
- Coil stays on after the CPU-side driver parts were replaced
- CPU and driver board transistors by position
- Testing driver transistors in diode mode (board out of game)
- When a driver fails, replace its pre-driver as well
- Auxiliary power driver board fuses
- Testing coil diodes on the auxiliary power driver board
- Outhole, Spook House target reset and flashers all dead: blown fuse on the aux board
Source: Repairing Williams System 11 Pinball 1986 to 1990, Deel 1, Clay Harrell (pinrepair.com)