Is it rebooting?

You know how system 11's boot up and for a split second the led's are solid before they start the flashing? Seems like it might be in a boot loop since it's flashing, but slowly.... so it's booting up, LED solid, then rebooting, LED is off, comes up, LED solid, etc.

When you booted it on the bench successfully 100% of the time was that with the game roms or a test chip?

You've handled all the caps connectors etc. on the power supply already?

I wonder if the reset generator you used is 'too fast' ?

Also, if you put nvram in it, you might have to jumper the 1n5817 diode out my whirlwind when I had it was like that.... didn't like the very tiny voltage drop of the 5817 (.2 volts instead of the standard .6 on a 4004)

You're going to have to replace parts that were hit with the battery damage. There is no magic cleaning the inside of the parts. It will migrate further.

I'm seeing the exact same thing happening. Plays fine for days, then out of nowhere 60 blinks and a garbled message. A power cycle brings it back to life. Did you ever find out the cause?

Ok, interesting. I happen to have ordered some ferroram already. I'll just hold off investigating further until that has arrived.

Question for you. What chip did you replace on the MPU board (at U what on the MPU board)? I understand the chip that controls the ram's enable line as stated above but where is that at on the board?

If you don't mind letting me know.

Thank you, I am having a similar issue and hoping this will help.

On boot up mine does the slow flashing on diagnostics but after about 15-20 seconds it finishes the boot up and plays normally. I may try replacing U35 and update if it fixes my issue as well. I will update when completed.

No acid damage on the board at all. Battery holdover was removed and NVRAM installed prior to me owning the pin. I have to order a 74SL10 chip at U35 once great plains opens up again as Ed is trying to catch up on orders.

Me too. @loren3233, how did this turn out for you?

My story since rescuing this barn find:

- Relocated batteries—leakage was significant. Three batteries of three different brands. One expired 20 years ago.
- Removed U41, used toilet bowl cleaner, water, alcohol to remove the alkali. My first time attempting this.
- Replaced 5 traces with cross connect wire
- Socketed U41
- Switch and lamp matrices working 100%, Coils good, some flashers needed attention (and were later fixed)
- A week or so went by, it seemed ok. As I worked on other problems I hit a wall when the lower left jet locked and I didn’t notice it until it was smoking pretty good. Coil and blown Q17 replaced, probes on Q13 and U18 seemed fine.
- The CPU was able to test fire the replaced jet bumper coil, but it was, for a time, unable to detect the switch on the jet. **I never figured out why and the problem went away.**
- Then another pop coil shorted and I caught it in time. A few pop switches were gapped too narrow—fixed.
- One time it came up dead. 5V LED only, no diag or blanking. Once it crashed and I watched the blanking and diag LEDs die over the course of a few seconds.
- Found a warming resistor on the interconnect board that had one end hanging loose. Coil 8C, one of the flashers. Fixed, probably not related.

Then the fun began.

- Blanking LED went out and I first saw the error reported by @zacaj. 60 slow-ish diag blinks, 10 faster blanking blinks, repeat. It never occurred to me before today that the display might receive useful information after the initial 60 flashes. Mine looked similar: garble on the left, “failure” on the right, flashing in tandem with the blanking LED.
- I found an exposed wire on the way up to the fan board that was in a position to intermittently short, which I found interesting given the intermittent boot failures I was grappling with. Fixed. Still wouldn’t boot.
- I spent some time tracing the memory protect switch. The tab was broken off the switch itself. Why? Reconnected it. Tried to trace it to somewhere meaningful on the MPU but didn’t succeed and dropped this thread. Time to pick this up again?
- Went through periods where it would survive hours on end of burn-in tests. During play tests it seemed to have trouble with coils involving the widget board. Fan and spinners and music would sometimes get mixed up or lock on or or not trigger. Then it went back to the 60/10 failure mode that started this thread and never recovered.
- This made me suspect U42, so I pulled it and did some cleaning. Repaired a couple of traces that I probably broke because I’m an amateur. Swapped U42 and U41 PIAs just to see what would happen.
- Noticed that pins 26-33 on the data bus going into the PIAs had continuity with one another, except pin 30. Tied pin 30 on U41 to pin 30 on U42. Not sure if this was a mistake.
- Same error condition applying power to the board (and nothing else).
- Installed Leon’s test ROM. All seven PIAs blink as expected.

At this point, why would I suspect a fault with the 74LS10 at U35 as discussed above? What should I try next?

Thanks friends. Let’s get this WW back into the world

EDIT: I’ve swapped known good ROMs into the game, and I’ve also swapped the widget and music boards. I’m tempted to resocket the ROMs or the CPU but not without a good reason.

EDIT2: A close up of the reset section makes it clear that I need to replace it as zacaj did, per the pinwiki documentation. I’m a little embarrassed to have gone through all this without addressing it first. Other suggestions welcome.
B40B7B08-1858-407E-BFB0-2C036F4286AF (resized).jpeg

How's the PSU looking? Are you getting a consistent 5 volt connection to the MPU?

Yep. And the behavior is the same hooked to a PC power supply on the bench. I’ll keep hacking at it…

I’m stuck on this.

Good:
- Board is on the bench, powered with a PC PSU
- Leon ROM boots and blinks the relay
- Whirlwind ROM boots enough to blink an error code
- Reset section cleaned up and replaced with a reset generator per pinwiki, it isn’t worse than it was before I guess

Bad:
- Whirlwind ROM blinks a pattern that isn’t documented. 60 slow diag blinks, 10 fast blanking blinks, repeat.
- Trace damage isn’t yet repaired to the point where I can connect the displays but I anticipate it would still look like post #7 above

Weird:
- I think when it was sort of working that I couldn’t prove that the memory protect line from the coin door was working correctly. Something in the back of my mind is saying “write enable.” I know how to use a logic probe but I don’t know what I’d be looking for.
- I thought perhaps it was a classic “adjust failure,” no meaningful data in RAM. I’ve got D1 and D2 in and confirmed 5V at the battery test point when power is off by way of an external battery pack. No change.

Should I look at PIA traces and reinstall the resistor networks leading to the display outputs, or should I look at something closer to the CPU?

Thanks all

Retest once you have all the traces repaired.

This was excellent advice. For Google: when your system11 pinball machine’s diagnostic light flashes slowly 60 times, followed by 10 quick “blanking” blinks, repeating forever, it might be because you have one or more PIAs on the main board that aren’t fully connected to the data bus. Check for evidence of current or prior battery leakage. If you find any, you’ll need to go through a full corrosion repair process. I managed to clean it up and repair the busted traces and my Whirlwind is back in action!