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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
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. OVERVIEW
The coolant system is to keep the engine temperature stable.
2. COMPONENTS
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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
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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
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1. ENGINE DATA LIST
Data Unit Value
Coolant temperature℃ 0.436V (130℃) ~4.896V (-40℃)
Intake air temperature
℃-40~130℃
(varies according to ambient air temperature or
engine mode)
Idle speed rpm700±50(P/N), 600±(D)
Engine load % 18~25%
Mass air flow kg/h 16~25kg/h
Throttle position angle°TA 0° (Full Open) ~ 78° (Close)
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 -
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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
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3) Injection Volume Control
(1) Overview
To keep the best engine conditions and to reduce the emission gas, ECU determines the injection
volume and timing.
(2) Components
Input Components ▶
Accelerator pedal
position sensorFront oxygen
sensorCoolant temperature
sensorCrankshaft position
sensor
Camshaft position
sensorKnock sensorT-MAP sensorElectronic throttle
body
Output Components ▶
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Coolant temperature
sensor
4) Ignition System Control
(1) Overview
G20DF engine is equipped with the single ignition system. Each spark plug is operated independently
by the ECU and one ignition coil and spark plug are provided for each cylinder.
(2) Components
Input Components ▶
Crankshaft position
sensorAccelerator pedal position
sensor
Knock sensorCamshaft position
sensorElectronic
throttle body
Output Components ▶
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(4) Features
Determines the ignition timing according to input signal
The ECU always analyzes the following elements when determining the ignition timing. 1.
Crankshaft position sensor
Camshaft position sensor
Coolant temperature sensor
Intake air temperature/air mass -
-
-
-
Warm-up of catalytic converter
The ignition timing is retarded for about 20 seconds to operate the catalytic converter according to the
operating temperature under the following conditions: 2.
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The idle speed is increased by the idle speed control to help warming up of the catalytic converter -
-
Idle speed control
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The ignition timing control can be performed faster than the control through the throttle valve.
Fuel cut-off in deceleration
The ignition timing is retarded temporarily to prevent abrupt increase of the torque when the
combustion is restarted.
Intake air temperature/coolant temperature
The ignition timing is retarded to prevent knocking if the intake air temperature or coolant temperature
is high. The ignition timing is retarded in the following cases. 3.
4.
5.
The intake air temperature is above 30°C.
The coolant temperature is above 105°C. -
-
The ignition timing retard for intake air temperature and for coolant temperature is added up for
correction.
ESP/ASR control mode
The ignition timing is retarded to reduce engine torque as fast as possible under the ESP/ASR
control mode.
Knocking control
If knocking occurs in the cylinder, the ignition angle of the corresponding cylinder is retarded. The
coolant temperature is 15˚C to 40˚C when starting. 6.
7.