Hi everyone. I recently brought home a working Gorgar and a non-working Flash. With the original boards in, when I first turn Flash on, I get both LEDs on the main board to flash once and go off, the displays flash very briefly, the GI lamps all come on, and there is a loud buzz through the speaker. If I turn it off and back on, I get a game sound from the speaker to go with the buzz, the two LEDs might flash once, they might stay locked on, they might not come on at all, or one of them comes on and stays on, the displays might show that it’s in audit mode, they might show some kind of random number, they might not show anything at all, or very rarely they show that the machine is in attract mode and I can coin up a game that immediately ends with the machine emitting the tilt sound and locking up again. I have to turn it off and on many times to get it to go into attract mode and even when it does, only a very small handful of feature lamps light. Most of the time, pressing the diagnostic button on the main board results in the top LED locking on. Sometimes, there is no response when pressing that button.

On the bench and in the machine, the board passes the first five tests with Pincoder’s adapter, it also will light most of the feature lamps with the adapter when tested. Likewise, it appears to pass all of the tests with Andre’s test rom. Here is a video of a test with Andre’s rom. In this video, the 5101 RAM was pulled so test 4 is failing. Notice that you can hear the flipper relay clicking loudly at the very beginning of the test and at the end when it is steadily clicking, but during test 6 where LEDs 3 and 9 are flickering on the test board, you can’t hear the relay cycling quickly. It does cycle but it sounds very muted like it’s being held closed. In every other video that I’ve watched, the relay clicks loudly during that part of the test. I’ve tried a second driver board and it does the same thing.

Last night, I pulled the MPU from Gorgar, swapped the ROMs and put it in Flash. I used one of the Siegecraft diagnostic switch boards because there was a key in the connector for the OE switches on the coin door so it wouldn’t plug into the system 6 board. I also put a 5101 NVRAM in it at the time and pulled the batteries. At power on, it went into audit mode. I turned it off and back on one time and got full attract mode. I added some credits and coined up a one player game. It played ball one for a while, then made the tilt sound, and the ball drained. When it kicked the ball out for what should have been ball 2 for a one player game, it showed that player 2 was up. It tilted that ball as well, then went to player 3. It tilted right away, went to player 4, tilted again, and then went back into attract mode, game over. I’m not sure why it would switch through tall 4 players players for a one player game. I’m not sure why every player got only one ball, but it started and at least helped me to figure out that my original main board is my problem #1. My PSU seems to be working. My driver board seems to be working to some degree too. I will figure that out once I get the original main board working. While I had the system 6 board in, I ran Andre’s test again. It responds exactly the same as the system 4 board except during test 6, when LEDs 3 and 9 are flickering on the test board, the flipper relay also cycles quickly and loudly, just like all of the other videos I’ve seen with Andres rom. With the original board, you can barely hear the relay clicking during that part. It's the same driver board in both videos.

I have a logic probe, an oscilloscope, a DMM, several Siegecraft test boards, a bench power supply, a decent soldering station, and three semesters of Electrical Engineering Tech. I used to be a television repairman, I’ve got this ultimate set of tools. I can fix it…but I’m going to need help.

The 40-pin interconnect has been changed at some point. There has already been a bunch of work to the MPU boards. The RAMs and ROMs are socketed. A lot of the bulletproofing has already been done. Given the above clues, where should I go from here?

Thanks!!

Thanks @cheddar. I knew of those test, but didn't think to try them out. I'll do that this afternoon and report back. The 40-pin seems to be OK by checking continuity with my meter between the boards for each pin. Each pin on the sockets for IC14, IC17, and IC20 all show there to be continuity between the same pins on each socket. Pin1 on IC14 shows continuity to pin 1 on IC17 and pin 1 on IC20 and so on.

Thanks again, I can’t pull the roms out with my fingers and I already changed one socket out with no change but I’ll look again. The 40 pin has already been changed at least once before I got it. It doesn’t look to be tarnished and it does take some effort to get the two boards separated.

Not that I see. The battery holder has been removed. Everything looks pretty clean. I'll post some pics this afternoon.

Thanks

I will do that but the sockets are already new. I found a pic on my phone. The one in the middle is the one that I changed since this pic was taken. Thanks again.
BADD5A8B-9F4A-4AA7-8398-82A0500A82E1 (resized).jpeg

Here’s a pic from before I removed the battery holder. It’s pretty clean.

38AA6F38-E6FF-43B8-AEB9-ACA85BF81F12 (resized).jpeg

I tried the ROMs in the system 6 board and was able to kind of play a game. I’ve looked at every solder joint for the 40 pin on both boards. No cracks at all. It’s all been done recently but I don’t know how recently.

According to the previous owner, it was working one moment and then it just quit outta the blue.

Thanks.

Stupid question of the day. What do the triangles on the schematic mean? I labeled them with a red circle. Is it Vcc?

1234 (resized).jpg

I knew the ground symbol, but I hadn't seen the up arrow symbol.

Cheddar I can’t get the socket tests to work. I burned the PATT2048 file to two 2716 chips. I put the first one in the socket for IC17 and the second in IC20. Both LEDs lock solid. Same when I use IC14 and IC17. The instructions say the top LED should flash if it passes. The bottom should flash if it fails.

Any advice?

So surprisingly, both sockets 14 and 20 failed. I’ll swap them out and try again. They’re both sip sockets. Do those go bad?

I also desoldered and resoldered the 40 pin.

Here’s a pic of the board with the battery holder removed.

image (resized).jpg

I replaced the sockets for ic14 and ic20. Now the pincoder adapter and andres test rom both point to a failure on ic13. Not sure if it’s due to a bad socket replacement or if the replacement highlighted another issue. The socket for ic14 was a real headache. Multiple pads on the bottom lifted off when I sucked the solder off. Two traces on the top had been “fixed” during the previous owners attempt at replacing that socket. I didn’t realize it until I had removed the old one.

I think I’ve got it all sorted out. I had to add some small jumper wires to fix the damaged traces. But I show continuity between each pin on all three sockets.

Are these boards multiple layers or just top and bottom?

That's exactly how I did it. When I sucked up the solder, several pads stuck to the end of my sucker.

I’m tossing in the towel for now. I might come back to this later. Now pins 9 and 10 on all three ICs are showing a short. I’ve pulled all three sockets. Ive quintuple checked for solder bridges. I pulled IC10 thinking maybe it was shorted. The boards is clear. I can’t find why there’s a short. Maybe I’ll come back to this in the future. Maybe I’ll punt it down the road and let it be someone else’s problem. Thanks for trying to help.