The motor-driven spinning wheel does not turn during play, although its lamp lights. Closing the motor relay by hand makes it spin fine.

Spinning wheel never turns in a game: faulty solenoid expander

Cause: The solenoid expander board that drives the relay had failed.

Checks

• Close the relay by hand: if the motor runs, the motor and its gear are fine and the fault is in what energizes the relay.
• Use the schematic to trace the relay coil back to its driver on the solenoid expander.
• Swap in a known-good solenoid expander from another Bally game; they are interchangeable apart from a game-specific jumper.

Fix

• Repair or replace the solenoid expander board, keeping the jumper setting the game needs.

Systems

• Bally MPU AS-2518-35

Games

• Fireball Classic

Related tips

• Pop bumpers fire nonstop after a solenoid expander swap: board jumper set wrong
• Solenoid expander relay buzzes or does not switch
• Dim controlled lamps and a buzzing expander relay
• Expander games: check the controlled-lamp power first
• How the solenoid expander board doubles up coils
• Test the coils behind the solenoid expander
• Replacing the hard-to-find 48 V expander relay
• The bulb next to the solenoid expander board must work

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