G3 AIO power/analog issue

[Enchanter Tim]

Any idea what could cause this? What should I be looking for? PSU issue? Analog board? I don't really know where to start.

I removed the boards, inspected everything visually and saw no obvious issues. No weak joints, no shorts, no bulging/leaking caps. I did buy a second AIO, but it's likely going to be a week or longer before it arrives. Figured I could swap PSU and/or analog board and see what happens and narrow it down.

https://drive.google.com/file/d/1SLXbic0axf_awXTaRIozKHrtoQtoRBKi/view?usp=drivesdk

 

[Enchanter Tim]

I removed the PSU, reflowed some joints, tested fuses and diodes, reassembled, powered the unit on and got a bong. Unfortunately, it shutdown and was no longer showing signs of life. Typically when clicking the rocker switch to On, it would produce a whine, but it's no longer doing that. Someone suggested it sounds like a resettable fuse. I'm letting the system sit for a day or so, waiting until the replacement logic board I ordered arrives and will test with that.

I also ordered some replacement ICs and relays (what I could source, since some are no longer manufactured). Doubtful these will be the cause, but I can at least rule them out. Next will be a full recap, and then... Probably just throw in the towel.

 

[Enchanter Tim]

New logic board made no difference (no surprise). The second AIO is en route; hopefully FedEx doesn't destroy it.

 

[Enchanter Tim]

The new AIO has a dead CRT. Swapped the PSU into the other system and it's working now. I've got a spare analog board amongst other parts in case I ever need them.