The ball hits a target, crosses a rollover or lands in a hole and nothing scores.

Rollover, target or eject switch does not register

Cause: Usually the switch is out of adjustment or its contacts are dirty; sometimes a broken wire.

Checks

• Find the switch (under the playfield for rollovers and holes, behind the target for targets).
• Close the blades by hand, or bridge the lugs with a jumper; if the game now scores, the switch is the problem.
• If it still does nothing, trace its wires to the board connector (solid-state) or relay (EM) for a break.

Fix

• Clean the contacts and bend the short (fixed) blade so the blades meet when the ball operates the switch.
• Straighten or remove misaligned fish paper, making sure the blades cannot short.
• Repair any broken wire.

Systems

• Williams System 3
• Williams System 4
• Williams System 6 / 6A
• Williams System 7
• Williams System 9
• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C
• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95
• Bally MPU AS-2518-17
• Bally MPU AS-2518-35
• Stern MPU-100
• Stern MPU-200
• Bally 6803
• Gottlieb System 1
• Gottlieb System 80
• Gottlieb System 80A
• Gottlieb System 80B
• Gottlieb System 3
• Data East CPU Version 1/2
• Data East CPU Version 3
• Data East/Sega CPU Version 3b
• Capcom
• Electro-mechanical

Source: Pinball Machine Care & Maintenance, Bernard B. Kamoroff (Bell Springs Pinball Alley)