Reflowed solder on the power board’s connector pins. Intermittent ground connections were causing the solenoid issues. Reflowed all board connector pins for preventative maintenance.

Checked fuse F2, the solenoids fuse. It is fine. Voltages are reasonable from power-on to first solenoid firing, and then they drop to surprisingly low voltages. Next steps: use a thermal camera to see if anything is heating up, and measure power flow.

Re-opened problem report

Did nothing meaningful really. Was messing with the action of the ball feed. At some point while fiddling with the machine all solenoids stopped working.

Replaced solenoid fuse and everything seems ok? Started the game several times and no issues with ball feed