A housing or pin is brown or darkened.
Discolored or heat-marked connector
Cause: Dirt adds resistance, which makes heat, which adds more resistance.
Checks
- Inspect connectors for discoloration.
Fix
- Replace both the board header pins and the housing pins of that connector.
Systems
Related tips
- Replace the 40-pin interboard female connector
- Remove terminal pins from a crimp housing
- Reusing an IDC housing needs 08-52-0072 pins
- Connector parts to keep for System 3-7 games
- Replace the 3J6 logic power connector
- Removing the old interboard female connector
- Replace CPU board power connector 1J2
- Always replace both halves of a connector
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part One, Clay Harrell (pinrepair.com)