Locking the second ball kicks one of the locked balls back out instead of feeding a new ball to the plunger, and multiball then starts with two balls instead of three.
Only two balls in multiball and a locked ball kicks out: sticky ball 3 lock switch
Cause: The switch for the third lock position was gummy and sticking, so the game miscounted the locked balls.
Checks
- With four balls installed, roll a ball into each lock position and watch each lock switch in switch test, making sure it opens again cleanly.
- Check trough optos and the trough for divots so the ball count is right.
Fix
- Clean the sticking lock switch and make sure its actuator moves freely.
Systems
Games
Related tips
- "Check Switch #" message at start-up
- Trough error at boot, games start only after jiggling balls: broken trough wire
Source: Pinball Repair help group!! (Facebook group)