Quoted from Quench:
R30 is directly across the base and emitter pins of the Q12 transistor. Note, this should have shown up as a bad reading when you were testing Q12.
Disconnect the J5 connector from the solenoid driver board so we don't lock any coils on during the following test.
Measure the voltage on the banded side of diode CR12 while you ground pin 10 (2nd top left pin) of U3. Then measure the voltage on the non-banded side of CR12 while grounding U3 pin 10. You should measure about 1.4 volts and then 2.1 volts respectively.
The thread I started if anyone wants to follow. I will be starting with readings from this test here.