Reseat the ribbon cables before chasing odd behavior
The ribbons linking the CPU board to the driver, Fliptronics, sound and display boards cause coils not firing, balls cycling and random coil firing, notably on Terminator 2, Star Trek: The Next Generation and Indiana Jones. Reseat them all on their gold headers before deeper work.
Systems
Related tips
- DMD shows a few dots and a coil fuse blows after reseating boards: ribbon off one row
- Every coil and flasher locks on after reassembly: aux driver ribbon cable reversed
- Several solenoids and a lamp group dead: reseat the CPU-to-driver ribbon
- Trough eject and left sling dead together: reseat the CPU to driver ribbon
- Slingshot also fires an outlane magnet: ribbon cable not fully seated
- Kicker dead in coil test plus a lamp row and column out: reseat the CPU to driver ribbon
- Gumball diverter, popper and two bumpers dead in test: faulty CPU ribbon
- All flippers fire at power-up and blow the 50 V fuse: aux board ribbon upside down
Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part Two, Clay Harrell (pinrepair.com)