The general illumination on the right side of the playfield is out.

Right-side playfield GI out: a wire not seated in a new power board connector

Cause: One wire in a newly fitted connector on the power board had not been pushed fully into its housing.

Checks

• Jumper the dead string's wire to a working GI string's wire: if the lamps light, the fault is on the dead string's feed.
• Check each wire in recently replaced GI connectors is locked into its housing.
• Check the GI relays (one in the backbox and one under the playfield) for welded or burnt contacts.

Fix

• Push the loose terminal home until it locks, or recrimp it.

Systems

• Williams System 11

Games

• High Speed

Related tips

• Pop bumper, sling and right-side GI lamps all go out at once: blown GI fuse
• Game resets when the flippers are used: recap supply and renew MPU power connector
• Half the backbox lamps and the lower displays dead: check the backbox fuses
• GI lamps out, game dark: burnt power supply connector 3J8 (pre-Banzai Run)
• Right chute lights flash once after power-up, then never again: bad lamp socket
• LED flashers glow or stay on: use bulbs in System 11 flasher sockets
• Resets continue after diode repair: power and connector checks
• What the System 11 power supply board feeds

Source: Pinball Repair help group!! (Facebook group)