A single digit on one player display shows garbage or flickers. Moving the display to another position moves the fault with it.
One display digit glitches and the fault follows the display: bad resistors
Cause: Two resistors on the display board had drifted to about half their marked value, upsetting that digit's drive.
Checks
- Swap the display with another player's display; if the fault moves, the display itself is at fault.
- Reflow the header pins first, since that is the cheapest fix.
- With the game off and the display out, measure the resistors around the digit driver circuit and compare them with their colour bands or with a good display.
Fix
- Replace any resistor that measures well off its marked value.
These displays run on high voltage (well over 100 V DC). Work on the display only with the game unplugged and let it sit before handling the board.
Systems
Games
Related tips
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Source: Pinball Repair help group!! (Facebook group)