Getting at the securing point for the cord inside the switch usually involves dismantling the switch contacts
and action. Not the rocket equation but not for the banana fingered either.
Replacement switch is simplest which as you say will need power and wires disconnecting anyway.
Once the defective switch has been safely isolated and removed you have nothing to lose by taking a look.
Be vigilant with wire connections for correct position and security. Crossed connections blow fuses at best,
loose connections overheat severely at that load current.
Asanewt
February 2009