The gate stopped opening when the lit top lanes are made, and does not fire in solenoid test either. The gate moves freely by hand and a new coil did not help.
Top lane gate never opens, even in solenoid test: failed driver transistor
Cause: The solenoid driver transistor for the gate coil had failed.
Checks
- Check the gate mechanism moves freely and its return spring is intact.
- Check or replace the diode on the coil.
- Ground the tab of the gate's driver transistor on the solenoid driver board (use the transistor map for the game) to see whether the coil fires.
Fix
- Replace the failed driver transistor on the solenoid driver board.
Systems
Games
Related tips
- Saucer fires at power-on and blows the playfield fuse: wrong coil killed its transistor
- Drop target coil fuse keeps blowing: shorted diode on the coil
- Bally -35: momentary solenoids all dead but fire when grounded: solenoid driver U3
- Coil in the drop target assembly is always on: burnt trace on the solenoid driver board
- No +5V on any board and no MPU LED: bad return pin in the solenoid driver board J3 plug
- Coils go weak or the wrong coil fires mid-game: reseat the solenoid driver plugs
- Knocker fires instead of the outhole kicker: bad solenoid driver J4 connector
- Kickout coil burns up in attract mode: driver transistor, resistor and the CA3081 at U3
Source: Pinball Repair help group!! (Facebook group)