Running into an issue with a board I just purchased. Installed a new Rottendog MPU004 (purchased from Pinballlife) into a Lethal Weapon 3 at a friends house. The original MPU was having issues with the flipper ground section of the MPU that couldn’t be corrected.

Moved over the 6802 and the ROM, and set the appropriate J4/J5 jumper for the ROM. Installed into the pin, everything boots fine, service menu accessible. Sound, lights, everything works perfect, including now the flippers, the issue that needed to be addressed.

Played several test games and now the scores will no longer display on the DMD consistently. All other DMD animations, including during attract mode are working and displaying correctly. If you play a 1 player game the score display is not shown the whole game, only the appropriate animations that occur during game play display correctly. If you play a multiplayer game the score display does show up after player 1 has played ball 1. Also once the multiplayer game ends the scores display are incorrect, a 100 is added to the front of the actual score. Everything else seems to be functioning 100% on the game, including the boot checksum.

I have tried swapping the MPU data cable to the DMD with a new one, but the issue continues. The game was not showing this issue with the previous MPU and the same 6802 and ROM, it only had dead flippers.

Any help y’all could provide would be appreciated. I’ve sent this info to Rottendog tech support, waiting on a response…..

I sent that one back and got a replacement board, that one wouldn't boot at all. I gave up on the RD boards and had the original MPU board repaired. Working perfectly now.