From an old forum post... may be helpful... “I would start by putting the machine into single lamp test mode. Then make a copy of the lamp matrix table from the manual, and cycle through all the lamps, marking them off on the matrix as you go. What you are looking for is a pattern of lamps that are lighting up incorrectly. You may find that you have an entire column that lights up at once when you should only be getting a single lamp. This should help you at least start the troubleshooting process.”

Interesting. I’d break out the multimeter and see if you have a short somewhere and or reflow the connector. Nice work tracking it down so quickly.