Soon after power-up one flasher lamp lights fully and stays on until the bulb burns out.

Flasher glows full bright until the bulb blows: shorted driver transistor

Cause: The driver transistor for that flasher on the power driver board had shorted (Q25 in this case).

Checks

• Find the flasher's driver transistor from the solenoid table in the manual and test it with the meter's diode test, board out.

Fix

• Replace the shorted transistor, then check the flasher's wiring and socket for a short before fitting a new bulb.

Systems

• WPC-95

Games

• Scared Stiff

Related tips

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