Page 514 of 1336

Problem Possible Cause Action
Coolant
level is too low
Coolant
temperature is
too high
2. INSPECTION
Leak from the radiator
Leak from the coolant auxiliary tank
Leak from the heater core -
-
-
Leak from the water inlet cap
Leak from the thermostat housing -
-Reconnect the hose or replace the
clamp
Change the hose -
- Leak from the coolant hose connections
Damaged coolant hose -
-
Change the gasket
Change the water pump -
- Leak from the water pump gasket
Leak from the water pump internal seal -
-
Tighten the bolts to the specified
torque
Change the cylinder head gasket -
- Incorrect tightening torque of the cylinder
head bolts
Damaged cylinder head gasket -
-Change the water inlet cap gasket
Change the thermostat sealing -
-
Coolant leakage (Coolant level is low)
Improper coolant mixture ratio
Kinked coolant hose -
-
-Add coolant
Check the coolant concentration
(Anti-freeze)
Repair or replace the hose -
-
-
Defective thermostat
Defective water pump
Defective radiator
Defective coolant auxiliary tank or tank
cap -
-
-
-Change the thermostat
Change the water pump
Change the radiator
Change the coolant auxiliary tank or
tank cap -
-
-
-Change the radiator
Change the coolant auxiliary tank
Change the heater -
-
-
Cracks on the cylinder block or
cylinder head
Clogged coolant passages in the
cylinder block or cylinder head -
-Change cylinder block or cylinder
head
Clean the coolant passage -
-
Clogged radiator core -
Replace the sensor or repair the
related wiring - Improper operation of cooling fan -Clean the radiator core -
Defective temperature sensor or faulty
wiring -Replace the cooling fan or repair the
related circuit -
Page 515 of 1336
2112-01
Problem Possible Cause Action
Coolant
temperature is
too low
Thermostat is stuck open -
Replace the cooling fan or repair the
related circuit -
Improper operation of cooling fan -
Replace the sensor or repair the
related wiring -
Defective temperature sensor or faulty
wiring -Change the thermostat -
Page 517 of 1336
2112-01
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. A.
Never open the cap until the coolant
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. B.
C.
D.
3) Thermostat
Immerse the thermostat into the water. Heat the
water and check the valve opening temperature.
Valve opening
temperature
Page 522 of 1336
Water pump
The water pump is driven by the engine drive belt and supplies
the coolant to each area of the engine.
Coolant reservoir
Thermostat
When the engine coolant
starts to open (fully open at
flow to the radiator to maintain
the engine temperature.
1. OVERVIEW
The coolant system is to keep the engine temperature stable.
2. COMPONENTS
Page 523 of 1336
2112-01
Coolant temperature
sensor
Measures the coolant
temperature and sends the result
to the engine ECU.
Radiator
Radiates the heat through fins and cools
down the hot coolant as the coolant
passes through the tube of the radiator
core.PWM fan
Circulates the fresh air forcibly to exchange
heat with the radiator core fin.
Coolant outlet port
Page 525 of 1336
2112-01
Coolant outlet port
to radiator
to water pump (bypass)
to cabin heater
to coolant reservoir
Coolant temperature
sensor mountinh boss
from cylinder head
Gasket A:
B:
C:
D:
E:
F:
G:
Coolant outlet port
Page 557 of 1336
1490-00
1. ENGINE DATA LIST
Data Unit Value
Coolant temperature
Intake air temperature(varies according to ambient air temperature or
engine mode)
Idle speed rpm
Engine load % 18~25%
Mass air flow kg/h 16~25kg/h
Throttle position angle
Engine torque Nm varies according to engine conditions
Injection time Ms -
Battery voltage V 13.5V~14.1V
Accelerator pedal position
1V 0.3~4.8 V
Accelerator pedal position
2V 0.3~2.4 V
Oxygen sensor mV 0~5 V
OCV (Oil Control Valve) % 0~100%
VIS solenoid valve 1=ON / 0=OFF -
A/C compressor switch
1=ON / 0=OFF-
Full load 1=ON / 0=OFF -
Knocking control 1=ON / 0=OFF -
Brake switch 1=ON / 0=OFF -
Cruise control 1=ON / 0=OFF -
Page 561 of 1336
0000-00
Rear oxygen
sensor
2) Components for ECU Input
Coolant temperature
sensorCamshaft position
sensorCrankshaft position
sensor
Front oxygen sensor
Knock sensor
G20DF Engine ECUElectronic throttle
body
Refrigerant pressure sensor
Clutch pedal signal
Blower switch signal
Brake pedal signal
CAN
ABS & ESP
Instrument cluster
TCU -
-
-
Oil pressure
switchOil pressure warning lamp
T-MAP sensor