Here's the excellent ECN schematic of a PSC motor: https://www.electrical-contractor.net/ubb/Forum15/HTML/000084.html

My question regards the failure of the run capacitor.

What are the usual failure modes for a PSC run capacitor... short to ground, loss of capacitance due to dielectric failure or...?

Would any capacitor failure mode cause the aux/run windings of the motor to fail due to excessive current or heat?