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The engine ECU calculates the accelerator pedal based on the input signals from various sensors, and
controls the overall operation of the vehicle.
The ECU receives the signals from various sensor through data line, and performs effective air-fuel ratio
control based on these signals.
The crankshaft speed (position) sensor measures the engine speed, and the camshaft speed (position)
sensor determines the order of injections, and the ECU detects the amount of the accelerator pedal
depressed (driver's will) by receiving the electrical signals from the accelerator pedal sensor.
The mass air flow sensor detects the volume of intake air and sends the value to the ECU.
The major function of the ECU is controlling air-fuel ratio to reduce the emission level (EGR valve
control) by detecting instantaneous air flow change with the signals from the mass air flow sensor.
Also, the ECU uses the signals from the coolant temperature & air temperature sensors, booster
pressure sensor, atmospheric pressure sensor to: a) determine injection starting point and set value for
pilot injection, and b) deal with various operations and variable conditions.
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2. COMPONENTS
Atmospheric pressure, RPM
signal * For details about control logic, refer to Chapter “Engine Control”.
E-VGT turbocharger
Improves engine powerAccelerator pedal position
sensor
Transfers driver's will to
accelerate to ECUEngine ECU (D20DTR)
E-VGT duty control
Coolant temperature sensor
Operates the VGT according to
engine warm-upT-MAP sensor
Improves the engine powerHFM sensor
Booster pressure and
temperature
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1. SYSTEM DESCRIPTION
1) Overview
The lubrication system supplies oil to each lubrication section to prevent friction and wear and to
remove heat from the friction part. As the engine runs, frictional heat is generated on each lubrication
section. If this condition persists, the bearing can be burned and stuck.
In other words, it creates an oil film on each sliding surface to convert solid friction to liquid friction in
order to minimize wear and prevent temperature increasing on the friction part.
For the D20DTF engine with no oil pressure switch, the engine ECU receives the low engine oil level
signal from the oil level sensor and communicates with the instrument cluster through the CAN
communication to turn on the warning lamp.
2) Components
Oil coolerOil dipstick gaugeOil pump
Oil filter moduleOil pressure switchOil pan
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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.
MT - 400W , AT- 600W
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10-4
1. OVERVIEW
The pre-heating system for D20DTR 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 plug
Engine ECU (D20DTR)Glow indicator
Glow plug control unit
(GCU)
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4) Operation
Glow plug is installed in the cylinder head. It enhances the cold starting performance and reduces the
exhaust gas during cold starting.
ECU receives the data (engine rpm, coolant temperature, vehicle speed) through CAN lines. Based on
the data, GCU controls the pre-glow, cranking and post-glow. It also checks the glow plugs, and sends
the result to ECU.
(1) Temperature/Current Properties of GCU
GCU increases the temperature of glow plug very rapidly (approx. 2 seconds up to
1000°C)
FETs (similar to transistor) for each cylinder are integrated in GCU. During the pre-glow
period, battery voltage is supplied to the glow plugs directly to heat them rapidly.
After getting the desired temperature by pre-glowing, the temperature is controlled by duty
ratio. Step 1:
Step 2 & 3:
Step 4:
This shows the supplying voltage and time by GCU in each step. The step 4 is the period to keep
the temperature. -Step 1: I1
Step 2: I2
Step 3: I3
Step 4: I4
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13-4
1. SYSTEM DESCRIPTION
1) Overview
The EGR (Electric-Exhaust Gas Recirculation) valve reduces the NOx emission level by recirculating
some of the exhaust gas to the intake system.
To meet Euro-V regulation, the capacity and response rate of E-EGR valve in D20DTR engine have
been greatly improved. The EGR cooler with high capacity reduces the Nox, and the bypass valve
reduces the CO and HC due to EGR gas before warming up.
Also, the engine ECU adjusts the E-EGR opening by using the air mass signal through HFM sensor. If
the exhaust gas gets into the intake manifold when the EGR valve is open, the amount of fresh air
through HFM sensor should be decresed.
Benefits of E-EGR valve ▶
Improved accuracy and response through electric control
Feedback function (Potentiometer)
Preventing chattering of EGR valve and improved durability
Self-cleaning function -
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-
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EGR pipe
Transports the exhaust gas from the EGR cooler
and EGR bypass valve to the intake duct.E-EGR valve
Receives the electric signal from the ECU to
control the valve.
E-EGR cooler and bypass valve
The cooler lowers the high temperature of the
exhaust gas and the bypass valve directly
supplies the exhaust gas to the intake duct
without passing through the EGR cooler to
reduce the emission of exhaust gas before
warming up the engine.HFM sensor
Used as a main map value to control the EGR.
The coolant temperature, engine rpm, engine
load, intake air temperature (HFM: decreased at
60˚C or more), atmospheric pressure
(atmospheric pressure sensor: altitude
compensation) are used as auxiliary map values.
2) Location and Components
See the section "Engine control" for E-EGR
valve control logic.EGR coolerEGR bypass
For details, see the section "Engine control".
*