System 7 GI harness break connector at the backbox
Many System 7 games have a connector that splits the playfield GI harness so the backbox can come off. It carries the 6.3 V AC GI on solid yellow and purple wires plus white wires striped yellow or purple and sometimes 12 V DC for under-playfield GI relays. Check it when a GI string is out.
Systems
Related tips
- Where the GI relay is on early System 6/7 games
- Lamp matrix wire colours and connector pins
- Burnt GI plugs on the power supply board
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two, Clay Harrell (pinrepair.com)