The left flipper locks on and its fuse or resistor blows. After replacing the coil, coil diode, MOSFET and its driver chip, the flipper works for a few flips and then the new MOSFET is shorted again.
Left flipper MOSFET keeps shorting after a few flips: counterfeit replacement transistors
Cause: The replacement IRL540N MOSFETs were counterfeit: they work briefly and then fail shorted. Damaged fine traces between the MOSFET and its nearby ceramic capacitors can also kill a new transistor, so check those too.
Checks
- Measure the flipper coil and compare it with the other side to rule out a shorted coil.
- Inspect the thin traces between the flipper MOSFET and its ceramic capacitors on the driver board.
- If everything checks out and the new MOSFET still fails quickly, suspect where the MOSFETs came from.
Fix
- Fit genuine IRL540N MOSFETs bought from an authorized electronics distributor, not loose parts from auction sites.
Systems
Games
Related tips
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Source: Pinball Repair help group!! (Facebook group)