The radiator fan relay is built in the relay box [A].

Radiator Fan Relay InspectionECU Power Supply Inspection
Remove the upper air cleaner housing (see Air Cleaner
Element Replacement in the Periodic Maintenance chapter).
Visually inspect the ECU connectors.
If the connector is clogged with mud or dust, blow it off
with compressed air.
Remove the ECU (see ECU Removal).
Visually inspect the ...
Water Pump Impeller Disassembly/Assembly
Remove the water pump impeller (see Oil Pump Removal
in the Engine Lubrication System chapter).
The sealing seat and rubber seal may be removed easily
by hand.
Apply coolant around the surfaces of the rubber seal and
sealing seat.
Install the rubber seal [A] and sealing seat [B] into ...
Radiator Cap Inspection
Remove:
Radiator Cap (see Coolant Change in the Periodic Maintenance
chapter)
Check the condition of the bottom [A] and top [B] valve
seals and valve spring [C].
If any one of them shows visible damage, replace the cap
with a new one.
Install the cap [A] on a cooling system pr ...