It should be fairly simple:
Light comes on while you´re at home:
Shut down, let engineering sort it out.
Light comes on while you´re away:
Pull the plug, check for particles.
If there are any: Take a good picture, and use some white tissue to save the chip to take it home with you.
Run up the aircraft again for a ground run (min.5-10 minutes).
light comes on again:
That´s it, you´re staying there...
Light stays off:
Continue flying.
Especially after an oil change or a change of components it is possible to get the light-that is what the engineering section is there for.
Oil samples can be sent in to be analyzed, and the lab can figure out where the particles are coming from....