[theWeezL]

only if they need replacing.

what 'nickel is saying is that if your fluid is low, AND its not leaking from somewhere, it COULD indicate that your pads and/or rotors are worn out. So he is suggesting you check your pads before just adding in more fluid and calling it good. The reservoir is fairly small on our cars, so it doesnt take much to make the light start coming on.

If you end up replacing the pads, your gonna be returning some fluid to the reservoir when you "open up" the calipers to fit over the new pads. So long as you dont have to bleed your brakes, it should return the fluid level to full.