Pulling the 1000-point relay in by hand advances the 1000s reel normally, but when the game scores 1000 the relay, the ball index and the 1000 chime all lock on and stay on through tilt, end of ball and end of game. It happens for every player.

1000-point relay, ball index and chime lock on: dirty score motor switch

Cause: A dirty switch on the score motor that is meant to break the relay's hold circuit was not opening cleanly, so the relay stayed energised.

Checks

• Clean and check the contacts on the 1000-point relay itself.
• Then follow the relay's hold circuit on the schematic to the score motor switch stack and check that the relevant switch opens as the motor turns.

Fix

• Clean and adjust the score motor switch contacts in the 1000-point relay's hold circuit.

EM games run some circuits on line voltage; unplug the game before working on the score motor and relays.

Systems

• Electro-mechanical

Games

• Monaco

Related tips

• 10 points and 500-plus-bonus don't score: dirty score motor switch 1C
• Score motor runs on at start, a reel locks on: mis-gapped reel switches and solder
• 1,000-point reels reset but never score for any player: failed 1,000-point relay coil
• EM: outhole kicks the ball back only once per game: dirty score motor index switch
• Score motor keeps running at game over, O relay stays in: score motor 2C switch
• Ball not kicked out of the outhole at game start: score motor 1D switch
• Player 1 hundreds reel steps only sometimes: dirty contact on the player 2 relay
• Reset relay stays locked on after scores reset: loose zero-switch arm on a score reel

Source: Pinball Repair help group!! (Facebook group)