After new connectors were fitted to the lamp boards, the playfield GI goes out now and then, mostly when a flipper is hit.
Playfield GI drops out when the flippers fire: loose ground wire near a lamp
Cause: A ground wire under the playfield had come loose near a lamp socket; the new connectors were not to blame.
Checks
- Remember the GI is AC fed from the rectifier board, not from the lamp driver boards.
- Look under the playfield around recently worked sockets for loose or broken wires, flexing them while the game runs.
Fix
- Resolder the loose ground wire.
Systems
Games
Related tips
- Maze lights flicker or go dark when flippers fire: loose fuse holder
- One drop target lamp won't light after board work: broken wire in the harness
- Mr. & Mrs. Pac-Man GI flashes in attract but stays off in play
- Several insert lamps stuck on after work on the game: corroded lamp board plug
- Lamp driver board layout: SCRs, decoders and connectors
- Lamp driver board: which SCR drives which connector pin
- Prove the lamp wiring by grounding the SCR anode
- Lamp always on: ground the SCR gate from TP2
Source: Pinball Repair help group!! (Facebook group)