Reels and steppers are clean, but pressing the replay button doesn't start a game.

Gottlieb reset-bank game won't start

Cause: Most often a dirty switch in the reset bank, especially on the S (start), game over or reset relays. Also: no credits (a credit unit switch opens at zero), coin door unplugged, hold relay not pulled in, or a score motor parked on a dead spot.

Checks

• Confirm there are credits.
• Confirm the coin door is plugged in; a Gottlieb won't even power up otherwise.
• Check the hold relay is in and its contacts are good.
• Nudge the score motor by hand with the game on; it should advance 120 degrees. Check its home switch.
• Flip up the reset bank and clean every switch, starting with the S and game over relays.

Fix

• Clean and gap the bad contacts.
• Resetting the bank by hand often gets a stubborn game going again.

Systems

• Electro-mechanical

Related tips

• Gottlieb start halts after reels reset: S Armature switch
• Start sequence of 1972-78 Gottlieb single players without a reset bank
• 1960s-1970s Gottlieb start sequence (score reel games)
• 1975-78 Gottlieb multi-player start sequence (Ax/Bx games)
• Using the start sequence to find where a reset stops
• Game never resets: bent coin door switch
• Starting a 1950s Gottlieb light-box game without taking a credit
• Start sequence of 1950s Gottlieb single players with light-box scoring

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