Simple faults relate only to PSEU, wherein the PSEU Light and OVHD system annunciator do not illuminate for simple faults unless a system annunciator panel is pushed for recall. In this case, a simple fault, resetting the MC system extinguishes the PSEU light.
On the newer ones we have the PSEU light automatically lights up 30 seconds after landing if a simple fault is present. Resetting the master caution system has no effect on the light. For a simple fault it extinguishes only when either the parking brake is set, or an engine shutdown.