Working on a non-booting Gorgar, and I'm starting to lose my mind a little. Here's a rundown. Hoping someone can offer up some advice!

Initial Analysis:
Powers up to GI, no boot, displays have glow, but blank. Checked fuses, Solenoid fuse blown, all others fine. Checked power supply voltages, 5.08V and 12V unreg seem fine coming off the power supply board. When the game is powered up, both LEDs on the MPU light up immediately, and stay lit. Power-cycling on/off quickly produces no change. A few times while turning the game on/off quickly, suddenly the relay on the driver board would click rapidly (insert lights flashed with it) and the displays would go crazy with junk digits/segments. This was rare, but happened a handful of times. A sound was emitted with it briefly. I have a video for reference, if desired.

Actions Taken:
- Verified voltage at CPU power connector 1J2 (under load) as follows:
12V unreg = 10.52 VDC
5V #1 = 4.82 VDC (note when connector is unplugged, this is 5.08 VDC)
5V #2 = 5.08 VDC
5V #3 = 4.82 VDC (note when connector is unplugged, this is 5.08 VDC)

- Interconnect replaced (both Male/Female)
- ROMs resocketed to get rid of dreaded SCANBE sockets
- Replaced RAM IC13 since that was a socketed chip

* No change after performing the above *

Following advice in other threads (including vid's guide, pinwiki, etc), I have tried several other things:

- Swapped in spare Power Supply I had, no change (correct voltages)
- Swapped in a spare System 6 MPU board I had around, same results
- Disconnected the Driver Board completely, and attempted diagnostics tests with MPU-only. Results were erratic, but after trial and error, pressing the Diagnostic switch on the MPU caused the LEDs on the board to flash and go out. Per info I found, this could indicate a Driver Board issue.

- Swapped in a spare, good Driver Board I had and powered up the game

* Game appeared to boot, and Display showed the Game ID, so I thought I solved the issue. Power-cycled the game on/off to get it to boot... and it immediately started doing the same thing it was doing at the beginning. Dead game, just GI, displays blank, both LEDs on the MPU locked on.

... What the heck happened? It's as if the other Driver board solved the issue, but then was immediately murdered somehow? I'm confused.

Help!?

I don't have access to a burner, can they be purchased easily somewhere? If someone is willing to burn me one, I can paypal/venmo cost+shipping

Also, would one of the potential issues kill a driver/game like that? Seems crazy to see it boot, then die after swapping in a spare driver board.

Thanks goingincirclez , fitting forum name for this kind of problem too ha.

I'm just concerned that somehow I killed a perfectly good Driver board, which seems crazy to me. I was really excited to see that Game ID pop up, and shocked when power cycling produced the same dead game all over again. I thought I had it sorted. I do have ONE more spare driver (clean, but unknown functionality) I could swap in there, but at this point I'm worried I'll kill it somehow.

I haven't used a test ROM before, but if someone can shoot me one for a little electronic cash, or direct me to an easy place to buy one, I'd be grateful.

Couldn't resist, tried my other driver board. No change, still not booting. I have no idea how it booted to game ID that one time, but I've had nothing since.

IC16 is not socketed, so I guess I could socket it and try a different ram chip there. But after trying two MPUs with the same result, I'm guessing that's not going to be the problem.

Some updates:

I socketed both of the RAM positions IC13 and IC16. I had four different compatible RAM chips, none of them seem to help completely, however with the current combination every now and then (maybe 1 out of 10 tries) I get flickering or random digits on the displays, and the relay on the driver board will lock on. It will sometimes stay that way, other times it will flake out some, causing the displays to flicker and relay to rapid fire.

Attempting to turn the game on or off, or do anything else, will usually put it back to being locked up with two LEDs on the MPU on.

Same results with either driver board I have on hand.

Not sure where to go from here. Can a PIA cause this behavior?

Here is a video of what it does when it doesn't simply not-boot. You can hear the driver board relay locking on as well. Normally I just get nothing, and two solid LEDs on the MPU. Sometimes I get this though:

Joydivision Thanks for chiming in, I appreciate it! I actually put electrical tape along the bottom of the CPUs because of that issue, having run into it with a previous System 6 game.

Going to take the boards over to a fellow enthusiast to have him help me take a look. Fingers crossed I'll have them sorted out by tomorrow night. I'll report back!

Gorgar Speaks! So it ended up being a flaky 5101 RAM. Testing showed something was screwed up in the RAM section, and since I had already taken care of IC13 / IC16, that was the only remaining possibility. It was a non-socketed chip, so it was removed and socketed. The weird part was once the same chip was put back in (using the socket now) everything was fine. I guess perhaps just a cracked/bad/cold solder joint when it was board-mounted. Everything checked and tested out great, zero issues with booting so far.

The speech board was bad too, but I was able to snag a replacement for a good deal, so everything is solid board-wise.

The only remaining issue is the Right Flipper is dead. I checked for voltage during attract and it's there for all 3 lugs on the flipper coil. Cleaned the flipper button switch and EOS, no change. I don't have high or lower power on the flipper when the button is engaged, so I'm not sure what's up. I tested for continuity between the flipper switch (Orange-Violet I believe) and the board connector, good to go there.

I forget, what's the trick for testing to see if a flipper coil will fire. I know I can ground a normal solenoid (or the transistor tab) to fire it and check wiring. There's a way to test fire the flipper coil too, right? Brain not working.

Perfect thanks. I hate when there's something I've done a couple dozen times and can't remember what it is. Much appreciated. I'll try that and see what happens.

frunch wouldn't that affect both flippers though? Or are they individually wired to the power supply. I would have to look.

I grounded the proper lugs and the coil fired as expected, so I'm good there. I tested the flipper button switch again just to be sure, and it's making good contact. Guessing I'm losing the ground side somewhere? Wires coming off are Orange-Violet and Blue-Violet from the flipper button side. I need to look over the schematics and see where everything is going, I guess. Very odd.

Good connection from 2J12-1 to flipper button switch, good connection from the other side of the switch all the way through the various connectors. Switch continuity good, even if I hook up back at the board end to test when I close the flipper button switch. I can always re-pin the connector, just in case, even though it's testing good. 36V at the coil lugs on both working and non-working flippers. 3J3-4 showing 18V when measured to GND (half of the 36 at the coil lugs, interesting).

Definitely seems like a really basic setup, so where the heck is the gap.

Usually a bad diode on the coil will blow the fuse, right? But that's not happening. I do have a spare new coil, so I could always swap that in just in case. Or I could just pull that diode off the existing and test it I guess.

Found it! See the pic for the issue, but basically one of the wires that was supposed to be going to the EOS for the right flipper was not connected. It must have come off and when the previous owner didn't know what to do with it, he shoved it into the wire harness clip. I pulled it out so you could see it, but that solder-blob end was literally inside the clip, so you couldn't see it. It was just part of the pile of wires going in there visually.

As for how I traced it out, I realized (duh) that the Blue/Gray (Left Flipper) and Blue/Violet (Right Flipper) wires coming from each of the flipper buttons would have continuity to the coils. When I found that on the Left Flipper, but not the Right, I knew there was a wire break or path issue somewhere on the Blue/Violet.

I saw the Blue/Gray for the working Left flipper went to the EOS, so I looked for the Blue/Violet on the EOS of the right side, and found nothing. I searched through the nearby wire bundles, and found it. A quick tug and there it was, dangling around, and hidden in that plastic clip. I jumpered over to the proper EOS switch lug and sure enough the flipper worked great. Just going to resolder it to it's proper home, and everything should be good to go!

Thanks all for chiming in!

Gorgar_DeadRightFlipper_Fix - Copy (resized).jpg