Quick lamp row test: ground the row driver tab
The lamp rows are driven by TIP122/102 transistors Q80 to Q87. With the game in a diagnostic test, clip a lead from ground to the tab of one of them: the whole row should light.
Systems
Related tips
- System 11 lamp matrix basics
- A row or column of lamps stuck on and very bright
- Testing lamp matrix columns with a test socket
- Lamp matrix still wrong after replacing transistors: upstream parts
- Whole lamp column works only intermittently: reflow the board header
- Lamps in two columns light together in single lamp test: failed lamp column transistor
- Quick check of all TIP122/102 drivers before first power-on
- Firing a coil or flasher from its TIP122/102 driver tab
Source: Repairing Williams System 11 Pinball 1986 to 1990, Part Two, Clay Harrell (pinrepair.com)