The upper right flipper chatters (buzzes instead of holding) when held up. A borrowed Fliptronic board cures it, so the fault is on the game's own board; replacing the flipper's driver transistors and swapping two chips from the good board made no difference.
Upper right flipper chatters, follows the Fliptronic board: wrong U2 and a bad D2
Cause: U2 on the Fliptronic board was the wrong part, and diode D2 had failed.
Checks
- Swap in a known good Fliptronic board to prove the fault is on the board.
- Compare each chip's part number on the faulty board with the parts list, and test the diodes in the upper right flipper's circuit.
Fix
- Fit the correct chip at U2 and replace the bad diode D2.
Systems
Games
Related tips
- Fliptronic flipper test points
- Flipper buttons stop working but coils fire in test: Fliptronic board switch plugs
- Fliptronic II board connectors and fuses
- Weak right flipper that survives a full rebuild: check for a bent base plate
- Fliptronics I appears only in The Addams Family
- Games that came with Type 1 flipper opto boards
- WPC flipper coils from weakest to strongest
- Flipper coil strength order (WPC flipper coil strengths file)
Source: Pinball Repair help group!! (Facebook group)