A 1970s Gottlieb game will not start or play correctly, traced to the Ax relay (single player) or Ax/Bx relays (multi-player).

Gottlieb 1970s Ax/Bx latch-trip relays misbehave

Cause: These short-frame latch-trip relays have very little switch travel, so a slight misadjustment stops them. Blades knocked out of their actuator slot and refitted in the wrong slot leave every gap wrong.

Checks

• Check each blade sits in its proper actuator slot.
• Check gaps closely on every Ax/Bx switch.

Fix

• Refit blades in the correct slots and adjust each switch precisely.

Systems

• Electro-mechanical

Related tips

• 1975+ Gottlieb won't reset: Ax/Bx latch relay blades out of their slots
• How latch-trip (interlock) relays work
• Gottlieb Ax/Bx/Dx relays, coin unit and player unit: what each does
• Start button gives a two-player game: wire on a latch relay touching another
• Gottlieb reset bank solenoid and S start relay run on 120 V
• Gottlieb 4-player shows players 1 and 4 lit at start
• Gottlieb player unit
• 1976 Gottlieb drop target games: score motor runs, AS relay stuck

Source: Repairing Electro-Mechanical (EM) Coin Operated Games to 1978, Part One, Clay Harrell (pinrepair.com)