Pull fuses F2 and F3 until the CPU board runs properly
While the CPU board is still being repaired, take the solenoid fuse F2 and the lamp matrix fuse F3 out of the power supply board. A crashed CPU or driver board then cannot hold coils or lamps on and burn them.
Systems
Related tips
- Pull the coil and lamp fuses for the first power-up
- Pull F2 and F3 when first powering an unknown game
- Bring a repaired board set back into the game
- A System 7 CPU board can run any System 3 to 7 game
- Run a System 6/7 CPU board on +5 V only
- Which CPU boards can run which system firmware
- Run Firepower on a System 7 CPU board
- Why the CPU LEDs stay on when the program does not run
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two, Clay Harrell (pinrepair.com)