Sigma Blackjack Breaks After Payout

[charlesge]

Hey everyone,

Unfortunately, posting here again since I seem to have broken something with my Sigma Blackjack machine that I can't get figured out. When the machine is in credit mode, after a run where the player elects to pay out their winnings, the game stops working and I don't know why. Coins drop straight into the hopper or back into the tray without adding to the credits, instructions button doesn't work, and the red test button on the inside doesn't bring me to the self test screen. I don't have a manual for this machine, but after doing some digging on the few Sigma troubleshooting threads out there on the web, I found Procedure 2 (image attached) lets me do a harder reset of the machine that brings it back to working normally (can see testing screen, plays fine) until the first payout.

The machine was working wonderfully before but this issue started after I started fiddling with it trying to figure out how to enable the surrender option in the menu. So, some possible leads:

• Fiddled with the white voltage adjustment pot on the power supply unit when I initially didn't know what it did. Reset it back to its original position more or less and checked with my voltmeter that I'm getting +5V and +12V at the right lines
• While fiddling with the power supply unit, at one point something shifted and the screen turned off and wouldn't come on subsequently when I turned on the power (lights would come on but no screen). This just went away after a couple minutes and it's been fine since, but I'm wondering if maybe I jostled a wire or something that's causing my present problem?
• Flipped the color and surrender dip switches in my attempt to change the game settings and that's officially how I got into this mess. After doing that I think I started getting this issue, although I messed around with flipping a lot more of the dip switches since so I'm not sure. I tried to reset everything and my current settings I've attached in a picture below.
• The issue seems to be correlated with an M-Door error. I got this problem at the same time the machine was giving me an M-Door error even when the door was closed. However, when the machine is hard reset and works (before the first payout), in the testing menu the door closed switch reads correctly.
• Flipping the dip switch setting from credit mode to coin mode has everything running fine. The automatic payout after a play doesn't brick the machine in coin mode.
• I think my issue seems closely related to the issue in this thread which pointed me towards the Procedure 2 hard reset. However, I can't find the purple wire above the main power switch that was causing that OP their problems.

Any help appreciated!

Charles