Tough situation on this one.

Bought a HH from a meticulous seller, everything worked. Disconnected the cables in the backbox, and brought it home.

Put it all back together, game fires right up and I’m playing. Second ball, I get it in the middle kicker on the top left of the game, and the ball doesn’t come out of the hole, the score displays go blank and the flashing lights stop. All I’m left with is an illuminated GI and and backglass. Sound is still working, flippers and solenoids dead.

Turn it off, turn it back on. Nothing. No display, no attract, no solenoids cycling. Just GI, Backglass and attract mode sound.

Two days of turning on and off and nothing I’ve done can get the game to boot up.

Fixes so far:
-Ground wires to boards already done
-Slam switch in door is closed
-Slam switch on PF is open
-Ball Slam Switch is open
-Gulf Pinball power board pulled and cleaned contacts
-Swemmer MPU board pulled and cleaned contacts
-Rottendog Driver board pulled and cleaned contacts
-Disconnected and reconnected all J molex cables. Added some Deoxit to ensure connection. Continuity exists in the cables
-Voltage at Displays read 60v
-Voltage at Power board reads exactly what’s needed
-Voltage at MPU reads 5v
-Voltage at Driver board reads 5v
-Fuses checked and DMM tested. All solid.

If there is a short, would that prevent a boot up? I don’t see anything around the kicker where it all started, but I’m not sure how to test for a short with a DMM.

I’ve ordered new pins to repin the cables but I can’t help but feel that the connections aren’t the issue here.

Any advice on where to go from here would be great. I’ve spent the last two days reading everything I can on Sys80 issues and none really describe this problem.

Thanks so much in advance.

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Orange cap was changed. Will check the rectifiers.

Update
Repinned J1 and J2 as well as A10-J5 because I found a wire out of one of the connectors. The game lights up as before but still no rom boot. The Backglass flashes like normal, the attract mode sound plays and the GI field is on. No game lights are on.

The power board is a Gulf Pinball Sys 80 MA-114
The MPU is a Swemmer 8T
Driver board is a Rottendog
Sound board is original Gottlieb.

Any suggestions are more than welcome.

I don’t have the option to test another board, and if there’s something going on that could possibly fry another board, I’m not going to take that chance.