The left gun kicker (01), left slingshot (09), left gun motor (17) and the underground exit flasher (25) stop working or work only in jerks, while every other coil and flasher works.
Solenoids 1, 9, 17 and 25 dead together: reseat the CPU to driver ribbon
Cause: These four outputs share the same data line (D0) from the CPU board, so a poor contact on the ribbon cable between the CPU and power driver boards takes them out together.
Checks
- In solenoid test, note whether the dead outputs are exactly 1, 9, 17 and 25 (one per bank).
- Inspect the CPU to power driver ribbon cable and its connectors.
Fix
- With the power off, reseat (or replace) the ribbon cable between the CPU board and the power driver board.
- If the fault persists, reseat the socketed chips on the CPU board.
Systems
Games
Related tips
- All flippers fire at power-up and blow the 50 V fuse: aux board ribbon upside down
- Every coil and flasher locks on after reassembly: aux driver ribbon cable reversed
- Cannons and a flipper lose power at once: a fuse that looked fine was blown
- After playfield work: optos, crane and Deadworld dead, trough dumps balls (J116)
- DMD shows a few dots and a coil fuse blows after reseating boards: ribbon off one row
- Underplayfield diverter coil burns and locks on: shorted Q15 on the aux 8-driver board
- Resets from worn power connectors between transformer, driver and CPU boards
- Solenoid numbers above 28 and the 8-driver auxiliary board
Source: Pinball Repair help group!! (Facebook group)