Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionCoolant Reserve Tank Installation
Install the following to the coolant reserve tank [A].
Pad [B]
Gasket [C]
Cap [D]
Collar [E]
Install the coolant reserve tank and tighten the bolt [F].
Run the hoses correctly (see Cable,Wire, and Hose Routing
section in the Appendix chapter).
Fill the coolant reserve tank with ...
Radiator Fan Relay Inspection
Refer to the Relay Circuit Inspection in the Electrical System
chapter
If the radiator fan relay is normal, check the wiring for
continuity, using the wiring diagram in this section.
Special Tool - Hand Tester: 57001-1394
If the wiring is good, check the ECU for its ground and
power supp ...
Air Suction Valve Inspection
Remove the air suction valve (see Air Suction Valve Removal).
Visually inspect the reeds [A] for cracks, folds, warps,
heat damage or other damage.
If there is any doubt as to the condition of the reeds, replace
the air suction valve as an assembly.
Check the reed contact areas [B] of ...