System 11 general illumination

System 11 GI bulbs run straight from the 6.3 V AC transformer winding and are not dimmed. On some games a relay fired by a coil driver output switches the GI off and on.

Systems

• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C

Related tips

• Right-side playfield GI out: a wire not seated in a new power board connector
• System 11 lamp matrix
• Backbox GI out, playfield GI fine: sticking relay on the backbox lamp board
• System 11 lamp matrix basics
• Half the playfield GI out: loose connector on the GI relay board
• Bulbs worth keeping on hand for a System 11 game
• Dim GI and backbox lamps: GI relays swapped for boards that were miswired
• LED flashers glow or stay on: use bulbs in System 11 flasher sockets

Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer