After a ball-path diverter coil burned, neither of the two special solenoids fires, and the flippers work all the time, even with no game running.

Diverter coils dead and flippers live at game over: 7402 at U50

Cause: The shared enable signal for the flipper relay and the special solenoids comes from a 7402 chip at U50; it had been damaged along with the drive transistors.

Checks

• Test the special solenoid drivers (Q77, Q79 here) and their predrivers.
• Test the 7402 at U50 in circuit with a logic probe before removing it.

Fix

• Replace the 7402 at U50 (after any bad drivers and predrivers).

Systems

• Williams System 11A

Games

• F-14 Tomcat

Related tips

• Coil fires when tested but not in game play: TTL driver chip
• Flippers and special coils all dead
• Special solenoid signal paths SS1-SS6 on the CPU board
• Right sling locks on at power-up and a pop is dead: bad 7402 at U45
• Logic chips for the special solenoid transistor pairs
• Damage after the black and white plugs were swapped
• How a coil or flasher is switched: PIA to TTL to pre-driver to driver
• A coil or flasher comes on and stays on at power-up

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