1972 Gottlieb King Kool I’m looking for help and guidance on how to repair this issue. My score motor keeps running when a ball is in the ball return hole. Once the ball is manually ejected the motor stops as well as the repeatedly firing O ball return relay. Also the play field is now “dead” and no scores, pops, flippers work. Playfield is fully illuminated, no tilt, but lights do flash on off when the ball is in the return hole. I have checked the ball return coil and it does fire when alligator wired to positive lead.

I do have the schematics and manual. Can relay any info to help. Thanks Cade

MarkG the solenoid fires so it’s still good and I can rule that out as the issue. Also before this issue I could fully play the game all three balls no issue just had to manually trigger the ZB first ball relay, if not the game would reset if a score was made. Replaced that coil and it works as intended (I think), since it triggers on when game is switched on.

Should the XB last ball relay be pulled in as indicated by the schematics to allow for the power to get to the ball return solenoid or do I have it backwards in my head

MarkG also i cleaned the U control back relay and XB last ball relay per your post. Both seems to be making correct contact on switches and make break switches.

Thanks. Cade

MarkG It fires when I jumper around from a positive on floor slam switch.

Ok the XB is closed correctly as the schematics show and stays closed when the bank resets.

Cade

I connected the jumper to the positive node on the ball return solenoid and to one of the open switches on the O relay. The solenoid does fire each time the O relay closes when the ball return hole switch is closed.

jumper wire still connected: Turned game off, tripped the OB game over relay, XB last ball relay, and ZB 1st ball relay. (I did this as if a game was just played and turned off). Turn game on, press start game, score reels reset, banks reset, and ejects ball to shooter lane and now no play field function. Is this still an issue with the ball eject circuit?

Sorry, your right. I guess I was trying to be to thorough and isolate the ball return circut to make sure it is operating correctly with the jumper.

Ok, so when jumper cable is attached the ball eject solenoid does fire when the ball return sw is closed, O relay closes, and score motor makes a 1/3 rotation. Does this indicate a short or bad wiring connecting the o relay and solenoid, and need rewiring. When not jumpered the motor continues to run and O relay continues to trigger.

On the ball hole sw it is connected to BR-WH and then on the o relay it is connected to what looks like the same color BR-WH. See attached photos for reference.

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Update: I think I found the issue using y’all’s pointers on jumpers and soloing out switches. The issue was before the U relay. The OR&GR wire was not soldered on well on the OB relay bank so power was never getting to the circuit. Now the ball return works as intended. Now on to the next issue. Ha!

Thank you all -Cade