Display fault: board or display?
Most games have five or six displays: four player scores, a bonus display and a credit/ball-in-play display. A fault on half of them points at the CPU board; a fault on one only points at that display. When two or more share a fault, start with the CPU chips nearest the display connectors: Z19, Z21, Z23 (7448) and Z17, Z24, Z26 (7404).
Systems
Related tips
- Use the shared wiring to locate display faults
- Brightening a display from the game's own supply
- Restoring brightness on 4, 6 and 7 digit display boards
- Displays are scanned, not lit steadily
- Gottlieb System 80: bottom segment missing on one display that follows it: replace Z1
- Brightening a dim Futaba display with a 9 V battery
- Guarding the fill tip on the back of a score display
- Gottlieb Futaba displays run on low voltage
Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part Two, Clay Harrell (pinrepair.com)