The coin lockout coil is always powered
The CPU has no control over the coin lockout coil: it is wired straight to the coil supply (about 25 V DC) and pulls in whenever the game is on.
Systems
Related tips
- Check every coil's resistance before first power-up
- Firing coils from CPU buffers Z6 and Z7
- Gottlieb coil wrappers are colour coded
- Why System 1 coils lock on: the ground shift
- Lamp test can hold coils on for five seconds
- First decide if the coil is CPU controlled
- A CPU controlled coil does not fire
- House-numbered coils need the chart, not the number
Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)