Closed problem report

After more probing and wiggling, we stopped being able to reproduce the problem. We’ll have to wait for it to come back.

Left lower flipper hold only works intermittently. Double flip is a symptom.

Using voltage meter and the logic probe, I compared left and right sides. They both seem the same at R29/R33, which I think is the logical signal for the hold circuit. But they differ at the pins on J802. This makes me suspect the TIP102 transistor at Q9.

I’m out of time to look, but I think the next question is whether it’s really that transistor or some intermediate component that’s intermittently messing up the control signal to the transistor.