This is my first post, please forgive the noob.

I bought a used Demolition Man in March 2021 at an auction. I found a few plastics that were broken and the diverter ramp wasn't hooked up, but all in all in played well. After performing a full shop on the playfield, fixing the plastics, hooking up the diverter, and upgrading to all LED lights (added a few LED strip lights from Comet) along with a new battery mod from TNT Amusements. The game was better than ever! Until recently a strange thing has started happening. I have done exhaustive research to try to find anyone who has experienced a similar problem. I've searched for an answer on Pinside and other forms hoping to find a answer so I wouldn't have to post this message, but I found nothing. So here goes. Please forgive me if this is something simple or just the way it's supposed to work... IDK?

After an epic 15 minute game I finally made it to Demolition Man Multiball and racked up some huge points. The next morning when the game was powered on a strange thing started happening. After the pop of the speakers and when the playfield lights come on during the initial start up tests of the cryo claw and the elevator, then game has now started launching balls. In fact in consistently launches 10 balls (5 twice) and then boots up normally and plays normally. Except for one thing... during every multiball it launches all 5 balls. Even Fortress multiball with only one ball locked (which should give you just two balls) it launches 5 balls. Crazy too is when the game sits idle for more than 10 minutes it starts launching balls again on its own, 10 balls launch then it stops and continues in low power mode. Also when exiting the options menu on the coin door the game restarts as usual but again launches 10 balls.

As a side note and at about the same time two flasher bulbs continuously stay lit. I have removed the bulbs to avoid melting plastic. I'm pretty sure the cause is a couple of bad semiconductors. Specifically Q16 and Q13. I have ordered new ones and will replace them once received.

Could it be a bad 7 through ball opto board? Marco part # #A-17982

Something with the ROM? or ASIC chip?

Thanks for your help.

Great advice! Thank you I will try that.

One more thing I just remembered... When all the balls have been removed and the game resets or powers back on, it launches 10 times, even with no balls.

So I did what LTG suggested and sure enough there was no signal for Opto #3. Perfect way to test the optos!! Thank you very much. Ordered a new opto and receiver board set from PINBALL HAUS. Will update when I receive it.