Remove the radiator cap in two steps. First turn the cap counterclockwise to the first stop. Then push and turn it further in the same direction and remove the cap.

NOTE
Wet the cap sealing surfaces with water or coolant to prevent pressure leaks.

NOTICE
During pressure testing, do not exceed the pressure for which the system is designed. The maximum pressure is 142 kPa (1.45 kgf/cm², 21 psi).
If the pressure holds steady, the system is all right.
If the pressure drops and no external source is found, check for internal leaks. Droplets in the engine oil indicate internal leakage. Check the cylinder head gasket and the water pump.
Remove the pressure tester, replenish the coolant, and install the radiator cap.
Coolant Deterioration Inspection
Cooling System FlushingRadiator 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 ...
Exploded View
25. “1T” marked side faces up.
26. “T2” marked side faces up.
27. Hollow mark faces exhaust side.
G: Apply grease.
L: Apply a non-permanent locking agent.
LG: Apply liquid gasket.
M: Apply molybdenum disulfide grease.
MO: Apply molybdenum disulfide oil solution.
...
Oil Pressure Relief Valve Inspection
Remove the oil pressure relief valve (see Oil Pressure
Relief Valve Removal).
Check to see if the valve [A] slides smoothly when pushing
it in with a wooden or other soft rod, and see if it comes
back to its seat by spring [B] pressure.
NOTE
Inspect the valve in its assembled stat ...