All the lamps on the board for pool balls 9 to 15 stay dark, while the 1 to 7 board works when plugged into the same connector.
Lamps for balls 9 to 15 never light: poor connector to that lamp board
Cause: A poor connection at the lamp board's connector.
Checks
- Swap in the other lamp board on the same connector to tell a board fault from a wiring fault.
- Inspect the connector and the board's header pins for cracked joints.
Fix
- Reseat the connector several times; for a lasting repair, reflow the header pins and repin the connector.
Systems
Games
Source: Pinball Repair help group!! (Facebook group)