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08-6
2) Leak Test
Release the pressure in the system by
loosening the pressure cap of the coolant
reservoir slightly. Then, remove the pressure
cap completely. 1.
Never open the cap until the coolant
temperature becomes under 90℃ to
prevent any burn.
Add the coolant so that the coolant level is
between MAX and MIN mark on the
coolant auxiliary tank.
Connect the tester to the tank filler and
apply pressure (1.4 bar).
Check all the coolant hoses, pipes and
connections for leaks when the pressure of
the tester drops, and replace or tighten, if
necessary. 2.
3.
4.
3) Thermostat
Immerse the thermostat into the water. Heat
the water and check the valve opening
temperature.
Valve opening
temperature 90±2℃
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08-71520-00
3. CAUTIONS
If 100% of anti-freeze is added, the water pump vane can be damaged and thermal
conductivity can be decreased resulting in poor circulation in the cooling system which leads
to overheated engine.
Use of non-recommended coolant could cause damage to the cooling system and
overheating of the engine.
Opening the coolant reservoir cap while the engine is running or hot can cause burns by hot
steam or water.
To open the coolant reservoir cap, wrap the cap with a wet towel or thick cloth after the
engine is cooled down sufficiently.
If cool water is added to the heated engine, the engine or radiator can be deformed.
The anti-freeze in the coolant can damage the painted surface, so avoid the contact of the
coolant to the painted body.
The anti-freeze and water should be mixed in proper mixture ratio. Never add only water
when adding coolant.
If the anti-freeze content is too low, the coolant can be frozen while the engine can be
overheated if anti-freeze content is too high. -
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-
-
-
-
-
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08-8
Oil filter module
Thermostat
When the engine coolant
reaches 90℃, the thermostat
starts to open (fully open at
100℃) and lets the coolant
flow to the radiator to
maintain the engine
temperature.
Water pump
The water pump is driven by the engine drive belt and
supplies the coolant to each area of the engine.
Coolant reservoir
Long life coolant is used.
1. SYSTEM DESCRIPTION
1) Overview
Water pump
Impeller vane Sealing
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08-91520-00
Electric fan
Circulates the fresh air forcibly to exchange
heat with the radiator core fin.
Radiator
Releases heat through fins and cools down the hot
coolant as the coolant passes through the tube of
the radiator core.
Coolant temperature sensor
Measures the coolant
temperature and sends the
result to the engine ECU.
Page 253 of 828
09-31451-01
1. SPECIFICATION
AlternatorCrankshaft pulley : Alternator pulley 1 : 2.94
Normal output (idling/2200 rpm) 70/120 A
Regulator voltage 14.6 V
BrushLength 12.5 mm
Wear limit 7 mm
BatteryType MF
Capacity 90 AH
Unit Description Specification
Page 254 of 828

09-4
2. INSPECTION
1) Alternator Output Test
Item How to check DTC set value / Action
Output
current
B terminal
current
Rotor
coil
resistance
L terminal
voltage
Disconnect the cable connected to the
B terminal on the alternator. Connect
one end of the ammeter to the B
terminal and the other end to the cable
connected to the B terminal.
Measure the maximum output value.
(Maintain the engine speed between
2,500 and 3,000 rpm.)
(Turn the headlamp and all the electrical
switches on.) 1.
2.Pass: If the measured current is
45 A or higher.
Fail: If the measured current is
less than 45 A.
Check the current of the B
terminal. -
-
-
Move the gear selector lever to the
neutral position.
Maintain the engine speed at 2,500 rpm
with the vehicle unloaded.
(Turn all the electrical switches off.) 1.
2.Open circuit: If the measured
current is 5 A or higher. -
Disconnect the negative cable from the
battery.
Remove the B terminal and turn off the
ignition switch.
Measure the resistance between the L
and F terminals with an ohmmeter. 1.
2.
3.Pass: If the measured resistance
is between 3 and 6 Ω.
Faulty rotor coil or slip ring: If the
measured resistance is less than
3 Ω or greater than 6 Ω. -
-
Connect the B terminal wiring.
Measure the voltage with the engine
running. 1.
2.Specification: 12.5 V to 14.5 V
Faulty IC regulator or field coil: If
the measured voltage is 14.5 V
or higher. -
-
Disconnect the negative battery cable.
Connect the negative cable again after connecting the ammeter. -
-
Page 255 of 828

09-51451-01
2) Troubleshooting for Alternator
Item Cause Action
Overcharged
batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or
open circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not
come on when
turning on ignition
switch with engine
stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp,
fuse or wiringReplace or repair the charge
warning lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace
Page 256 of 828