Hi all. I’m looking for help in getting a Williams 1985 Space Shuttle System 9 solenoids to work. Here is what I’ve already done.
Never had any working coils since I bought this game.
Blown fuses on F2 (2-1/2a fuse) so once a good fuse was installed I observed immediate coil lock on when power on.
Quickly shut off power and cut wires to that coil (#6 drop target bank of 3) Power on again and a different coil locked on
(#7 up post between flippers).Repeated cutting wires off to that coil and tried again. Now a 3rd coil locked on (#13 Gate)
Power off and cut wires to that coil. Finally power on and no other coils locked on.
I run a solenoid test and now get 5 coils to fire in test mode. Never had any fire before this. Coils 1, 3, 5, 8 and 15 fire.
I have attached solenoid table for reference.
I know that transistors must have been blown so I run ohm test on all large transistors relating to solenoids by doing what I call “The Grumpy test” that I found on archived posts. Put red lead of DMM to ground and black lead to large tab on transistors and checked ohms while game is powered on and connectors J11, J12 and J19 are not connected.
Thank you Grumpy for teaching me that method!
4 transistors are out of range (reading nil) so I replace all 4 and now all transistors test fine.
Power off, reconnect J11, J12 and J19 and power on again. No blown fuse, no lock ons. Previous coils cut off are still off.
All is good(?)
I test ohms on ALL coils. All are in range except the 3 that I cut off earlier. Put new coil on #6 and #7 and solder on. I don’t have a replacement for #13 gate coil yet so I leave wires off and tape ends to avoid any shorts.
Power on one more time. No lock ons, no blown fuse but no solenoids fire in test mode. Tested bridge rectifiers on back box wall and they are both good. I have already cut off coin door coil in the beginning because I don’t need coin door eject for home use.
1 last thing not sure if it is relevant to this. The F1 (1/4 amp) fuse on power board continues to blow even after all this. I have replaced original displays with XPIN replacement displays and display board. Pulled connectors off new display board and F1 fuse still blows