This is an ongoing problem and I just keep chasing rabbits and barking up the wrong tree. Maybe the video will help someone lead me in the right direction. Rarely does the game just fire up but follow my routine in the video and see how I manage to play a few games before it decides to crap out.
I get 1 flash on startup. According to my research, 1st flash tests the CPU Ram on U1. Therefore, that component is good. The 2nd and 3rd flash sequence is validating the program ROMs at U2 & U3. I have changed the bases on both of these, ordered new game ROMs, reflowed each pin and still cannot get consistent play. After I tap on each chip, turn on the game and within 3 tries I usually get it to complete a 9 sequence flash cycle. I can usually get through a few games before it suddenly freezes up. The gamefield will look like it does at the start of the video. There doesn't seem to be any rhyme or reason for the freeze up as I've had it do it while in play, in attract mode, and when the ball is just sitting in the shooter lane. The CPU is a new Swemmer board and I have replaced most of the plug sockets. New power board, displays, and reconditioned soundboard. ANY help will be greatly appreciated.

pinball 1 flash small (resized).png

Thanks, i'll check the video. Yes, I repinned the connectors.

Sorry about no sound and slow start on the video. I was describing the problem but the sound didn't get recorded.

This is what I found about a -35 board. I was wondering if the U7 chip does the same thing on a 6803 board?
no second flash fakers guide (resized).JPGno second flash fakers guide (resized).JPGno second flash fakers guide (resized).JPGno second flash fakers guide (resized).JPGno second flash fakers guide (resized).JPG

Ya, that's where I'm kinda stuck. Get one flash. The second and third flashes are for the game ROMs and I already replaced the bases and ROMs. I don't know if there is another secondary chip that is being accessed and preventing the game from booting. I also don't know if the tapping on the board is actually doing something or it's just coincidental and I just happen to get a signal to latch on and continue to boot when I turn it back on. Thanks for the help.