Flasher fuse F111, coil fuse F112, or the main line fuse blows.

F111, F112 or the line fuse keeps blowing

Cause: Bridge BR3 (coils) or BR4 (flashers) has shorted, or a shorted flasher socket, coil, relay or motor. Repeated F111 or F112 failures mean the driver board is probably damaged.

Checks

• Test BR3 and BR4.
• Disconnect playfield connectors to see whether the fault follows the wiring.

Fix

• Replace the bridge or the shorted device; repair the board if fuses keep failing.

Line voltage is present in the power box and at the transformer whenever the game is plugged in; unplug it before working there.

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)

Related tips

• Which fault blows which driver board fuse (WPC-89/WPC-S)
• Fuse F116 keeps blowing
• Finding whether a blowing fuse is a board or wiring fault
• Gun calibration never finishes and cannon won't move: check fuse F111
• F104 and F112 blow at start-up: auto-plunger coil wire touching its bracket
• F112 then F103 blow after a socket shorted a switch: isolate to the supercharger board
• Switch matrix fuse F115 (F101 on WPC-95) blows as soon as it is replaced
• F11 blows after a few games: shorted flasher leads on J122

Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part One, Clay Harrell (pinrepair.com)