The flippers can be flipped in attract mode, before a game is started. Everything else works normally, and the fault goes away when a different solenoid driver board is fitted.
Flippers work with no game started: faulty Q15 on the solenoid driver board
Cause: The flipper relay is being held on because its driver on the solenoid driver board is stuck on. Here transistor Q15 had a cold solder joint and was also defective; swapping the flipper relay itself made no difference.
Checks
- Listen for the flipper relay clicking in as soon as the game powers on; if it does, its driver is turning it on when it shouldn't.
- Swap in a known good solenoid driver board if one is available to confirm the board is at fault.
- Check Q15 on the solenoid driver board and its solder joints; compare it with the other driver transistors with a meter.
Fix
- Replace Q15 on the solenoid driver board and reflow any cracked joints around it.
Systems
Games
Related tips
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- No coils work at all though fuses are good and game starts: 43 V not reaching playfield
- Knocker fires instead of the outhole kicker: bad solenoid driver J4 connector
Source: Pinball Repair help group!! (Facebook group)