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08-70000-00
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 o
r
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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08-8
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.
1. SYSTEM DESCRIPTION
1) Overview
Coolant reservoir
Long life coolant is used.
Water pump
The water pump is driven by the engine drive belt and supplies
the coolant to each area of the engine.
Oil filter module
Water pump pulley Impeller vaneSealing
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08-90000-00
Coolant temperature sensor
Measures the coolant
temperature and sends the
result to the engine ECU.
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.
Page 216 of 1082

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. -
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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. -
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09-50000-00
2) Troubleshooting for Alternator
Item Cause Action
Overcharged battery Defective alternator voltage regulator Replace
defective alternator detection wiring Repair or replace
Discharged battery Loose alternator drive belt Adjust the belt tension or replace
Poor connection of related circuit or
open circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator Replace
Terminated battery Replace
Defective ground Repair
Charge warning lamp
does not come on when
turning on ignition switch
with engine stoppedDefective alternator voltage regulator Replace
Open circuit in charge warning lamp,
fuse or wiringReplace or repair the charge
warning lamp or fuse
Defective ignition switch Replace
Defective ground of alternator circuit Repair
Charge warning lamp
does not go off after
starting engineDefective alternator voltage regulator Replace
Corroded or worn battery cable Repair or replace
Loose alternator drive belt
Adjust the belt tension or replace the
belt
Defective wiring harness Repair or replace
Page 220 of 1082

09-8
(3) Starting with jumper cable
If the battery is weak or terminated, the battery from another vehicle can be used with jumper cables to
start the engine.
Connecting order ▶
The positive (+) terminal of the discharged battery
The positive (+) terminal of the booster battery
The negative (-) terminal of the booster battery
Connect one end of the other jumper cable to the body of the discharged vehicle, such as the
engine block or a front towing hook. 1.
2.
3.
4.
Starting ▶
Prepare a set of jumper cables.
Place another vehicle that has the same 12 V of power near to the discharged vehicle.
Switch off all electrical accessories for the discharged vehicle.
Apply the parking brake and shift the transaxle to the P position (automatic transaxle) or neutral (N)
position (manual transaxle).
Connect the jumper cables.
Try to start the discharged vehicle while accelerating the engine rpm in the booster vehicle.
Attempt to start the engine with the discharged battery.
After starting the engine, carefully disconnect the jumper cables in the reverse sequence of
connection. 1.
2.
3.
4.
5.
6.
7.
8.
Page 222 of 1082
09-10
Battery
It converts the chemical energy to the
electrical energy and supplies power to the
corresponding electric units when starting
the engine.Alternator
The alternator charges the battery and
supplies power to each electric unit by
converting the mechanical energy to the
electrical energy.
1. SYSTEM DESCRIPTION
1) Overview
The charge system is designed to supply electrical energy to the vehicle while driving, and supplies a
constant direct current voltage by converting mechanical rotational movement to electrical energy.
The voltage regulator on the back of the alternator controls the generated voltage in all rotating ranges
and adjusts the system voltage according to the electric load and ambient temperature change.
2) System Layout (Locations)
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10-51413-00
1. OVERVIEW
The pre-heating system for D20DTF engine has the glow plug to the cylinder head (combustion
chamber), and improves the cold start performance and reduces the emission level.
The pre-heating resistor (air heater) is used to heat the intake air.
This enables the diesel fuel to be ignited in low temperature condition.
The ECU receives the information such as, engine rpm, coolant temperature, engine torque, etc.,
through CAN communication during pre-heating process; and the pre-heating control unit controls the
pre-heating, heating during cranking and post-heating by the PWM control.
Glow plugGlow plug control unit
(GCU)
Glow indicatorEngine ECU (D20DTF)