What changes when fixing coils on System 11
Use the WPC coil method (ground the coil, then the driver tab), but remember System 11 has no help screens, likely uses A/C banks, and runs coils at both +25 V and +50 V. First check whether the game has an auxiliary power driver board; without one, every 50 V coil goes through a playfield relay board.
Systems
Related tips
- System 11 coil outputs
- 50 V coils on earlier System 11 games
- Where the coil diodes are on System 11
- Fitting a replacement coil on System 11
- 50 V coils on early System 11: under-playfield relay boards
- Checking for power at a coil
- What a bad coil diode does
- How the System 11 A/C bank select works
Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer