First Post, Need assistance S6000 keeps tripping 1 5amp Circuit Breaker

[Sdultra]

Hi All,
  Have to say reading through these forums has been a great experience.  Thanks to all for sharing your expertise.  I have an S6000, that has been working just fine, until it tripped the lower right 5a circuit breaker.  I have read every thread I can find, and tried everything suggested, but I am still at a loss.  Here is what I can say:


1. If I power up with the MPU removed the breaker does NOT trip.
2. I disconnected everything from the backplane to see if one if these items was the cause of the short, but to no avail.  With everything disconnected the MPU still causes the breaker to trip.
3.  I swapped the breaker with a different breaker just to make sure the breaker wasn't week, still no joy.
4. I checked the voltages on the bottom left of the backplane and all voltages were correct.
5.  I removed the power supply box and checked both power supplies visually and I don't see any bad components or capacitor leakage, and besides that with the MPU out all voltages read correct from the backplane .
6.  I inspected the MPU for any obvious component damage but again I cant visually identify anything wrong.


7.  this problem occurred while the machine was on, but idle.


Any thoughts, ideas, tips, prayers etc. would be greatly appreciated.


Thanks

[Sdultra]

After more troubleshooting, I can tell you that it is the 21Vac circuit that is tripping the breaker.  I haven't been able to determine exactly what the 21 vac is used for as I do t see it anywhere is the wiring schematics for the MPU.


At this point I am hopeful that either the transformer or the main power supply are the root cause as they are less expensive than replacing the MPU.


Still, any expertise, thoughts or ideas would be appreciated.

[pbwizard25]

Check the wiring to the coin chute diverter coil. This has got me a few times also. Scott

[Sdultra]

Thanks Scott. Seems to be fine. The relay energized momentarily before the breaker pops. If I disconnect the relay nothing changes either.
Appreciate the idea though.

[Sdultra]

Well I thought I would post another update.  As the Power Supply and Transformer did not do the trick, I order up an MPU board.  Low and behold it was the MPU board that was the source of the problem.  Migrated my chips over and now have a fully functional game again.


Question, where can I find schematics of the S6000 MPU board?  Since I know the issue is with the 21 VAC , I thought I might be able to find the faulty component and repair the old board as a spare.  Anyone??


Regards!