More than 8 mm
Radiator Fan, Fan Switch, Fan Relay
The fan switch monitors the water
fan switch is open when the temperature is below the
specified level, and conducts when the temperature
exceeds the predetermined level.
The fan relay controls the power supply to the fan
motor, and permits the fan motor current to flow only
when the fan switch is conducted.
The radiator fan draws air through the radiator core
when there is not sufficient air flow, such as when the
engine is idling. This speeds up the cooling action of the
The shroud is provided to prevent the air
recirculation around the ends of the fan blades, which
causes the loss of fan efficiency.
Cooling Fan System Circuit
If the radiator fan does not turn when the water
temperature gauge swings to the right side of the water
temperature gauge, either the circuit of the water
temperature gauge or the cooling fan system is defective.
Cleck the cooling fan system as following.
NOTE: Refer to Pgs. 262 - 263 for the inspection of
the water temperature gauge.
Pull off the fan switch lead, and ground the lead to
the engine with a suitable lead. If the fan turns, the
cooling system except for the fan switch works properly,
and the fan switch should be inspected. If the fan does
not turn, there is a fault in the fan, fan relay, fan
switch, or wiring.
This fan blades can cause injury. Be very
careful to not allow any
wire lead to touch the fan.
Fan Switch Lead
B. Ground the lead.
Radiator fan inspection
Remove the fuel tank, and visually inspect the
radiator fan. If the fan blades or shroud is damaged,
replace the part.
Disconnect the 2-pin connector of the fan leads, and
connect the black fan lead to the battery
and the blue fan lead to the battery + terminal. If the
fan does not turn at this time, the motor is defective and
must be replaced.
A. Bleck Lead
Bettery - Terminal
B. Blue Lead to Battery
Fan relay inspection
eRemove the fan relay from under the fuse box.
eMeasure the relay coil resistance using an ohmmeter as
Table H87. If the resistance is out of the
specified range, replace the fan relay.
Relay Coil Resistance
One meter lead
The other meter lead