Banzai Run blowing fuses and transistors

[Hammerhead]

I'm hoping someone can help me diagnose a recent issue with my BR.

Lately transistor Q22 and fuse F2a (2.5A SB) have been blowing during coil test:
- all coils test fine until it gets to coil 16 (left eject hole), where I this coil does not fire
- on the next cycle through the coil tests coils 01A (outhole kicker), 02A (ball shooter lane feeder), 05A (flipper post, upper playfield) and 08A (centre eject hole) no longer fire, and the right most flasher on the head stays lit all the time (transistor Q22 has blown) - note that coil 08A (centre eject hole) is also controlled by Q22

Here's where it gets interesting:
- schematics show that there is a common brown wire (switched solenoids) to 01A, 02A, 05A and 08A and it is that way on the game
- schematics show that there is a common red wire (controlled solenoids) to coils 9 10, 11, 12 15 and 16 (left eject hole), but 16 is in fact brown and connected to the other four switched solenoids.

Anyone with a BR could you please check the wiring to see if the left eject hole does have a brown wire and not a red wire. The other wire should be brown-grey.

Otherwise, there must be a short somewhere but I can't isolate it.

 

[Hammerhead]

One other thing to note is that, when I replace the F2A fuse and then turn the game on, the fuse blows again, but not before you hear a loud bang (like the knocker going off) on the right side of the cabinet under the flipper button. This is also where the line filter box is located.

 

[IVPinball]

Yes, brown and brown grey

 

[Hammerhead]

So that suggests the left eject hole is actually a switched solenoid, not a controlled solenoid as per the schematics. What other coil would it be switched with I wonder?

 

[atariaction]

I now own this machine and am taking over where Hammerhead left off. Steve can you summarize the current state of the machine cause I'm sure I'd leave something out. Also I believe you sent me an email suggesting that you were sure the issue could be related to 1 of 2 coils but I cant find that info anywhere.

If I were to summarize the issue (from what I understand/remember):

Transistor Q22 and Fuse F2A (2.5aSB) keep blowing in solenoid test. 5 solenoids (and 3 flashers) are all tied in here. The fuse is associated with the 5 coils and of those coils Q22 controls oA8 "center eject hole" solenoid and the 3 flashers.

We are suspecting a ground short could be the issue. The game was used in league and worked fine before so this is a new issue.

All coils were measured and tested fine.

Someone on Maaca suggested the following:

I would test the following 3 diodes on the Aux Pwr Driver board,
with machine power Off, and a Multimeter in diode check mode.
You probably should disconnect plug J1 on the Aux Pwr Driver board too for the diode test
- D8
- D43
- D44
and check for any cold solder joints, especially around pins & traces used by D8.
It appears D8 is functionally the diode across the coil thing.
If that diode is opened or shorted, It would blow the drive transistor.

The machine wont fit in my basement so it is at my friends and before I go over there I want to be armed with all the info and suggestions I can get before I really dig in. Any help is appreciated. Thanks!

 

[sylvain]

I had suggested the above D8, D43, D44 check over on MAACA - using the game manual schematics.
The other side controlled by that Q22 transistor are flashers - according to the manual p.73:
6 of 6 (U)/cap. (L) Flashers.

- Sylvain.

 

[atariaction]

Great thanks will do. I follow up to this point "6 of 6 (U)/cap. (L) Flashers". What does that all mean?

 

[sylvain]

Great thanks will do. I follow up to this point "6 of 6 (U)/cap. (L) Flashers". What does that all mean?

I was wondering the same thing, then realized the answer is in the game manual on p.59, look at item 08C,
e.g. 6/6 ramp captive ball left flashers it appears.

The picture clearly indicates the flashers location under the main playfield.
Check to ensure the flash lamps sockets/wiring are not shorting to ground,
in addition to the diodes and coil thing for the 08A side driven by the same Q22 transistor......

- Sylvain.

 

[atariaction]

Ok sounds like a good plan thanks!

 

[Hammerhead]

I now own this machine and am taking over where Hammerhead left off. Steve can you summarize the current state of the machine cause I'm sure I'd leave something out. Also I believe you sent me an email suggesting that you were sure the issue could be related to 1 of 2 coils but I cant find that info anywhere.

If I were to summarize the issue (from what I understand/remember):

Transistor Q22 and Fuse F2A (2.5aSB) keep blowing in solenoid test. 5 solenoids (and 3 flashers) are all tied in here. The fuse is associated with the 5 coils and of those coils Q22 controls oA8 "center eject hole" solenoid and the 3 flashers.

We are suspecting a ground short could be the issue. The game was used in league and worked fine before so this is a new issue.

All coils were measured and tested fine.

Someone on Maaca suggested the following:

I would test the following 3 diodes on the Aux Pwr Driver board,
with machine power Off, and a Multimeter in diode check mode.
You probably should disconnect plug J1 on the Aux Pwr Driver board too for the diode test
- D8
- D43
- D44
and check for any cold solder joints, especially around pins & traces used by D8.
It appears D8 is functionally the diode across the coil thing.
If that diode is opened or shorted, It would blow the drive transistor.

The machine wont fit in my basement so it is at my friends and before I go over there I want to be armed with all the info and suggestions I can get before I really dig in. Any help is appreciated. Thanks!

That's got it in a nutshell. the coils are daisy chained together and the flashers are connected via relays, so they are all related and likely one issue is causing all the problems. These issues only reared their head when I was testing the game in preparation for sale. Up to that point it actually hadn't been turned on since the last league night.

The reason I suggested one of two coils (left hole kickout and centre hole kickout I believe) was that when I last went through a solenoid test, the coils on that daisy chain worked fine. Once the test got to one of those two coils, Q22 and F2A blew and now none of the coils on that daisy chain work and the flasher 6/6 is locked on.

 

[atariaction]

Awesome thanks Steve!

 

[Hammerhead]

From another thread:

For the record, this turned out to be a bad Q22, pre-driver Q18, U19 and U28. The centre eject hole coil lugs were making contact with the coil bracket just barely - it was installed facing forward instead of to the side. Over time, this resulted in a cascading storm of nastiness that took out the board components. Fortunately, the PIA was spared.

 

[atariaction]

Haha I was going to update this thread but corey could have not said it any better

 

[Hammerhead]

Great to hear it was an easy fix Who would have thought with all that going on it would play so well at league a few months back.

At least you know you now have a rock solid machine.

 

[atariaction]

Haha. That was only about 5 hours!!!

These issues obviously happened after league night but that is weird how it happened.

I hesitate to call any nineties machine Rock Solid seeing as how pinball is pinball LOL. And My Philosophy is "it is working untill it is not" but I am certainly happy of the current state

 

[atariaction]

Well 1988. Close!

 

[Menace]

That's pinball baby! These things are designed to break... regardless of age. If you don't like it, find another hobby to sink your time and money into.

D

 

[Hammerhead]

Like classic cars, they never break down. Considering how much I have invested in my basement right now, might even be cheaper too.

 

[atariaction]

Haha yep! If one wants less hassle and expense I recommend Dominoes or Tidlywinks!

 

[Menace]

Like classic cars, they never break down. Considering how much I have invested in my basement right now, might even be cheaper too.

I'm screwed... I've got pins and a classic car!

D