Pull F2 and F3 when first powering an unknown game
A coil can lock on at power-up and burn both itself and its driver transistor. Until you know the CPU is running properly, remove solenoid fuse F2 and lamp matrix fuse F3 from the power supply board.
Systems
Related tips
- Pull the coil and lamp fuses for the first power-up
- Pull fuses F2 and F3 until the CPU board runs properly
- First power-up check on a dead game
- Bring a repaired board set back into the game
- Power circuits in a System 3-7 game
- Where flipper power comes from
- What the power supply board takes in and puts out
- Replace the 3J6 logic power connector
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Three, Clay Harrell (pinrepair.com)