Hey everyone! Still working on bringing this pin back to life and it hasn't been easy. Yesterday I was just doing some final adjustments with the flyaway targets and various other minor playfield issues. All of a sudden after working on this thing for about three weeks, Adding coins was troublesome. Reflowed solder over the connectors and that seemed to resolve it. Today I lost nearly all lamp with exception of the GI. Three lamps stay on all the time, even in test mode. Coin mechs are doing the same thing whereby all three coin switches do not register. I jumpered directly from the board pins to the coins switches giving the same results. All test points giving proper results. Is the MPU on the fritz? Any ideas? Seem unrelated but happened at same time.

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Playfield fuses are good.

I am getting correct flashes on MPU. Also, I swapped pia chips at u11 and u10, no change in its behavior. It could be connectors, but I doubt as I have attempted to jumper directly with no avail. I also reflowed pins. If I had another good MPU I'd give it a go. Do the scrs work like a transistor?

I actually was working on the flyaway targets. That's when things went downhill.

Pulling j2 or j3 on the MPU does not change symptoms.

Displays function. I don't have a logic probe. My only resource is a DMM at the moment. Most switches register as closed if I close during switch test. A handful along the right side are not working. It would come at no surprise that I cannot close any of the coin "in" buttons. Credit reset functions. Occasionally, the right saucer will say it is closed when it clearly is not.

Another point of note is that when this happened, I lost a few lights that scroll in attract mode in the back box that I believe are driven by the aux light board. This again points to problems on the MPU, or at minimum connectors from that source. I think I will order me some fresh .100 and .156 connectors and start there. I appreciate all of your comments and suggestions. Keep them coming no matter how simple or obvious. Often times its the simple things that get over looked in these cases.

1.

Cut all the wires going to flyaway switches. No changes

2.

Switches that will not close in test are right rollover star, inlane joker, right inlane special. Of course all three coin ins.

3.

They flicker during MPU led flash test. Once you get the MPU fired up and a "ding" from sound board they stay on. So no, the do not fire immediately

4.

No resistance is measured without lamp. With about 2.5 to 4. No differences between various lamps.

5.

U1 pin1 .3v
U1 pin2 2.1v
U1 pin3 1v
U1 pin23 2.2v
U1 pin22 2.1v
U1 pin21 2.2v

U2,3,4 at pin 23 read 2v

Thank you so much for the help. I assume pin 1 in u1 should read higher?

1. Lamp was blown at 3k spinner. New lamp stays on the same as other three now.

2. Spinner will not close. Not sure on tilt or slam, did not have time to check. Btw, right star switch was not working prior to this issue.

3. No stuck switches during test.

I will check others tonight. Thx again, might be onto something here.

Oddly, slam and tilt will close during switch test? Pin 3 reads 1v, while all others read about 2v. That's in attract mode both with connectors on and off.

This board has had some work to repair battery damage. It does not appear any work has been done to replace sockets or anything like that.

We've tried removing the j1, j2, j3 connectors and pin 3 of u10 is still 1vdc.

I still have just a few lamps on in attract mode. 7 to be exact.

I noticed c58 had one leg broke off. I believe it is in the display circuit. Soldered it back down and it did not change the symptoms of the game.

The game worked for a few weeks so I'd say it is unlikely a soldering mistake was made. I can try to replace u20.

Flat 1v on dmm

Hey guys, I pulled cr1 and it restored a lot of the attract mode lighting. I don't believe it's all back but it's better. Any ideas on the switch matrix?

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Unfortunately everything in circuit checks out. .6v at cr1. Blocks signal in opposite direction as the diode should. R111 shows 55k as do nearby resistors. C42 and the nearby caps measure out the same.

The pin 3 of u10 is now at 2.1v. I still have lights in attract mode along the right line as well as the entire bottom half of the playfield.

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Here is an update.

Well I bit the bullet and purchased a brand new Alltek MPU. Sadly, the machine exhibits the very same problems. No response from coin in switches. Nothing from right rollover star or card six up top (those haven't worked since I have owned the machine). Joker inlane and a few others now work. Fortunately I can start a game with free play mode.

The lights are exactly the same as they were a few weeks ago. Nothing along the right side or the bottom half of the machine.

Clearly we have been chancing our tails exploring problems on the MPU.

What is next? Any ideas? Light board?

Ground issue on lights.