First power-up check on a dead game
Steps
- Finish the power supply, connector and socket work first; the supply must give correct voltages.
- Remove the backglass so the CPU LEDs (or System 7 digit) are visible.
- Pull fuse F2 (solenoids) and F3 (lamp matrix) on the power supply board.
- Power on and note what the CPU LEDs do, then use the matching symptom entry.
- If the LEDs never light at all, check for +5 V reaching the CPU board.
Systems
Related tips
- The usual causes of a dead System 3 to 7 board set
- How a good System 3 to 7 CPU behaves at power-on
- Power a System 3 to 7 CPU board on the bench with a PC power supply
- Game always powers up in audit mode: bad 5101 memory chip
- Is it the CPU board or the driver board? Boot the CPU alone
- System 3/4 CPU: no clock at the 6800 or MC6875
- System 6/7 CPU: no clock at the 6802/6808
- CPU LEDs (or System 7 digit) never light at power-up
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two, Clay Harrell (pinrepair.com)