After some work on the game, the bottom thumper bumper and both outkicker switches stop registering, though the wiring looks intact and nothing shows closed in switch test.
Pop bumper and both outkicker switches dead: bare wire touching the coin door
Cause: A bit of bare wire near the coin door was touching the metal door, shorting the switch line those switches share.
Checks
- Find which matrix row the dead switches share, and check that line's continuity from the MPU connector to each switch.
- Look for bare or damaged wire anywhere along that line, especially where harnesses run past the coin door and other metal parts.
Fix
- Insulate or repair the bare wire so it can't touch the coin door.
Systems
Games
Related tips
- Closing one switch kills the whole column: slam tilt switch touching the coin door
- Flipping scores 10 points: a rebound switch squeezed closed by new rubber
- Switch reads stuck closed, or a pop bumper chatters
- Tilt doesn't work and closing it fires a pop bumper: dirty slam tilt switch
- One switch or a string of switches never registers
- Bonus multiplier advances on bumper hits: hair-trigger mushroom switch
- Switches register with the wrong numbers
- Several playfield switches drop out together: worn insulation shorting the start button
Source: Pinball Repair help group!! (Facebook group)