Weird S2000 Power Issue

[smddms]

This machine has sat for about 10 years. The last time it was played, it worked fine. I was all set to replace the coin cell battery, but the machine initially would not power up. Turning the switch on would cause the power to "blip". It would act like it was starting for a split second then turn off. A few seconds later, it would do the same thing. The door lights, vfd, fluorescents, leds on cpu, candle and topper lights would all just blink for a split second then turn off.

I decided to pull the plugs from the motherboard one at a time to narrow down the issue. Once I got to J8, the machine started up normally. It ultimately threw the "meter disconnected" error. In this state, I was able to replace the coin cell battery, clear and key, and completely set up the menu options.

Things I have tried to resolve the issue:
1. Replaced the cabinet I/O board with one from a working machine.
2. Swap out CPU with one from a working machine

Machine details:
5 reel "Triple Lucky 7" 9 inch cabinet with topper
504 rev B board with enhanced sound board. Green battery was removed long ago. Has a coin cell battery holder.
5 cent coin handling
Bill validator
Ticket printer

Has anyone experienced this issue? Looking for some guidance on what else I can check. The issue seems to be related to the cabinet I/O. I thought replacing the board would fix the issue, but it looks like it's deeper. I tried to upload a video, but it was too large. 

Thanks for reading.

Steve

[sixcardmark]

Your title may have the answer: Power issue.  Test or replace the power supply, it's behind the reels. Check that it is making good contact (check thumb screw on left side). Videos must be uploaded to youtube or similar, you can only post pics here under 1mb in size.

[smddms]

Thanks sixcardmark. I will have a look at the power supply and swap one from my other working machine if I see any anomalies.

[Retro tech repair]

Caps in power supply dried out while being stored.

[smddms]

I was able to swap power supplies with my other working 5 reel machine. The power supply from the machine I am having problems with was able to power my working machine without issue. The power supply from my working machine did not change the behavior of the machine I am having an issue with. 

I will work on getting a video posted of the issue.

[Retro tech repair]

I was able to swap power supplies with my other working 5 reel machine. The power supply from the machine I am having problems with was able to power my working machine without issue. The power supply from my working machine did not change the behavior of the machine I am having an issue with.

I will work on getting a video posted of the issue.

You have a major short in the cabinet then my experience it’s usually a florescent light ballast.

[smddms]

I was finally able to upload a video of the issue: https://drive.google.com/file/d/1F8i2FdprDcbjEvFCF04dre9tDFz6eo8V/view?usp=sharing

[smddms]

I unplugged the fluorescent ballasts for the door, cabinet, and topper lights. The behavior was still the same as in the video I posted, except the fluorescent light no longer blinked for a split second when the machine was turned on.

I also tried disconnecting the bill validator, meters, and backlit reel controller, but that made no difference as well. I believe all of those run through the cabinet I/O board.

[lookes]

Have you tried removing the hopper? It is powered through the cabinet I/O card. Also, unplug the reel backlight cable from the front of the card. Never remove or replace I/O cards or any cables while the power is on! 
Other devices attached to the cabinet I/O card are the candles, handle switch and release solenoid. Check all wires and inspect the back of the card holder on the MPU cage.  To check the cable from the backplane to the I/O card, remove the I/O card and see if the machine powers up.

[Retro tech repair]

Have you tried removing the hopper? It is powered through the cabinet I/O card. Also, unplug the reel backlight cable from the front of the card. Never remove or replace I/O cards or any cables while the power is on! 
Other devices attached to the cabinet I/O card are the candles, handle switch and release solenoid. Check all wires and inspect the back of the card holder on the MPU cage.  To check the cable from the backplane to the I/O card, remove the I/O card and see if the machine powers up.

I have seem the handle lock solenoid shot out often.

[smddms]

Thanks lookes and Retro tech repair along with everyone else who responded. I was able to get past the power issue. It was a short. I pulled all the plugs coming from the cabinet I/O board one at a time and it turned out to be the candle. The wire was frayed and touching the cabinet. Thanks again to everyone.

Steve