Repair

The Machine This Bally NBA Fastbreak (1997) came in purchased from a home owner who had kept it for over 20 years. The game was in great cosmetic condition, but had some gameplay and sound issues that needed solving. A good starting point, the cabinet and playfield were in great condition. Battery Corrosion The game had battery corrosion, though thankfully WPC-95 machines use a plastic battery tray instead of an open frame holder, so the damage was far more contained than what you’d typically see on an older WPC game. Corrosion was cleaned and abated before anything else was touched. Again people, check your batteries regularly! These had expired over 10 years ago! ...

The Machine This Williams High Speed 2: The Getaway (1992) came in with two issues — strings of GI lighting were dead or dim, and the game would occasionally refuse to boot. Both turned out to be related to the same issue — bad IDC connectors. The Problem The factory IDC (Insulation Displacement Connector) headers used on WPC games are notorious for failure over time where high current is involved, usually the GI strings and input power to the driver board. As they age, contacts loosen, get pitting or corrosion in the plating, the connection resistance increases, which generates heat. The heat degrades the connector further, which generates more heat — a cycle that eventually ends with a melted, burned connector and dead GI strings or boot/reset problems. ...

The Machine This Williams STTNG (1993) came in needing attention on all the classic STTNG things; trough optos, the left gun mech, the main opto board, and a poor prior LED swap all needed addressing. STTNG is probably the hardest WPC game to maintain is which is unfortunate, as the game is really fun to play (when it’s working well). Trough Opto Repair Trough opto failures are extremely common on WPC widebody machines. Over time the opto board connector solder joints crack and fail, or the opto pairs themselves just die and stop reliably detecting balls. All trough opto connectors were reflowed, which resolved most of the issues — but one opto pair was still reading marginal after the reflow and had to be replaced outright. It’s still worthwhile to repair these boards as a set of new widebody trough boards are still $100 for some reason. ...

The Machine This Stern Guardians of the Galaxy came in with a seized Groot jaw lock mechanism, with a $80 driver board that had paid the price for it. What Happened The Groot jaw mechanism uses two alignment rods and a motor with gearbox to open and close the jaw for ball locks. Both rods are retained by two e-clips, and on this machine, one of the upper e-clips had broken and allowed the rod to fall out of position. With only one rod in place, the jaw lost alignment, rotated some and eventually bound completely. ...

The Board This WPC-89 MPU came out of a Judge Dredd. The game had stopped booting entirely and was showing intermittent direct switch issues before it gave up — two classic symptoms that point straight to MPU corrosion damage. Diagnosis On WPC-89 MPUs, battery corrosion is one of the most common failure points. The onboard batteries leak if not replaced often, and the corrosion spreads across the board under the batteries, taking out the switch matrix components and traces underneath. In this case the corrosion had only reached U16, one of the LM339 comparator ICs responsible for the direct switch inputs, which explained the switch issues prior to the full boot failure. ...