I agree with whats said. But power down is a last resort which I use about once a year. Normally Cb trip and reset does it. The computor performs a power up test and if OK you are done. But on B777 the status msg will still be there. You have to erase it manually via Maint pages chap 31. Also on B777 and B744 a test via the Central Maint Computor is usually better.(and quicker because most CBs are downstairs) On A319/20 CBs are quicker.
Also be very careful of engine faults. They will normally clear on the ground, and then come back again on start up! The fault is held in the FADEC. Clearing the display in the cockpit doesn't clear the fADEC.