I have a 49 shuffle alley deluxe with 50 flip pin head on it. Worked flawless for years. Recently, 1-9 step unit stuck solenoid, blew the fuse. I replaced the fuse, game worked for 15 min then solenoid stuck on again. If I rotate the wheel around by hand it unlatches after approx 2/3 revolution. Now when I power up the machine the score motor just keeps spinning with the 1-9 step unit solenoid latched. Any suggestions?

Thanks for the info. I have checked over all the step up units and I think functionally they are all ok. I disassembled the 1-9 step unit and cleaned it. And checked it 100% and I think it's ok. Had to adjust the backlash on the sprocket via the solenoid stop and it seems to be in good alignment.
When I power up the machine the score motor just rotates continuously and 1-9 step up locks the solenoid on with a loud humm/buzz. If I manually rotate the 1-9 step sprocket it reaches a spot where something in the connections shuts off the solenoid.
While all the buzzing is going on the score motor continues to rotate, each revolution cycling the strike/spare solenoid. Once I get the 1-9 stepper to stop locking up I can simulate scoring, hitting the playfield, then the puck return switch and it will score and allow frame changes normally until the game is over. Then when I reset to play again it starts the misbehavior over again...... Can't figure it out.