The flipper-controlled mini playfield moves strongly to one side but only weakly to the other.
Mini playfield tilts strongly one way, weakly the other: clean and reflow its opto board
Cause: Dirty optics and poor solder joints on the opto board that tells the game where the mini playfield is.
Checks
- Watch the mini playfield position optos in switch test while moving it by hand.
- Inspect the opto board for cracked joints, and reseat the related ribbon cables.
Fix
- Clean the optos and reflow the solder joints on the mini playfield opto board.
Systems
Games
Related tips
- Games that came with Type 2 flipper opto boards
- Flippers, mini playfield and optos dead with endless ball search: blown 12 V fuse
- Indiana Jones: Path of Adventure stutters when moved with the flipper buttons
- One switch also triggers others in its column: bent diode on the mini playfield
- Mini playfield switches misread and one switch shows as another: bad diode and miswire
- Indiana Jones: no optos work, check J905 on the Fliptronics II board
Source: Pinball Repair help group!! (Facebook group)