A fluid supply apparatus includes a fluid pump for supplying a fluid to a
fluid supplied portion from a fluid storage portion, a pair of passages
provided between the fluid storage portion and the fluid supplied portion
in series with the fluid pump, one of the pair of passages including a
first supply passage with a check valve therein for preventing the fluid
from flowing back to the fluid storage portion from the fluid supplied
portion and the other of the pair of passages including a second supply
passage provided in parallel with the first supply passage, and a
switching apparatus for switching the second supply passage to a state in
which the fluid can flow in the second supply passage.