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.
On this machine, a GI harness connector at J115 on the power driver board had burned to a crisp. The connector was severely melted with exposed, uninsulated connections. The harness connector at J101, the input for the regulated 5v rail was also burnt and was causing the occasional boot failures.
Repair
After replacing both GI and transformer secondary connectors with a KK Molex connector, the GI and boot issues were resolved. The U turns on the GI connectors are optional once you swap to Molex, but i decided to try and keep them where possible.
See below for before and after pictures, especially noticeable in the backbox where incandescent lights were still being used.
Result
Replacing both burned IDC headers with a proper Molex connector restored brightness to the dim GI, and the boot issues disappeared entirely. If your early WPC game has dead or dim GI strings, always inspect J114-J121 first — a melted connector is one of the most common issues on these earlier WPC machines, and should be done any time you work on a WPC game.
Note: If you own a WPC game, it’s worth inspecting all GI connectors periodically for heat damage or if they are getting warm. Replacing aging IDC headers before they fail catastrophically is cheap insurance against a much bigger problem.