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03-26
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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06-171914-01
1. SYSTEM DESCRIPTION OF E-VGT
(Electric-Variable Geometry Turbine)
The E-VGT turbocharger has one shaft where at each ends are installed with two turbines having
different angles to connect one end of housing to the intake manifold and the other end to the
exhaust manifold. As the turbine, at exhaust end, is rotated by exhaust gas pressure the impeller,
at intake end, gets rotated to send air around center of the impeller, being circumferentially
accelerated by the centrifugal force, into the diffuser. The air, which has been introduced to the
diffuser having a passage with big surface, transforms its speed energy into the pressure energy
while being supplied to the cylinder improving the volume efficiency. Also, the exhaust efficiency
improves as the exhaust turbine rotates. The turbocharger is often referred to as the exhaust
turbine turbocharger.
1) Overview
Diffuser: With the meaning of spreading out it is a device that transforms fluid's speed energy into
the pressure energy by enlarging the fluid's passage to slow down the flow.
The E-VGT system installed to the D20DTR engine variably controls the passages of the turbine
housing to regulate the flow rate of the exhaust gas. The actuator of E-VGT is a DC motor
actuator (E-Actuator) which controls more quickly and precisely than the previous vacuum type
actuator.
The engine ECU controls the E-Actuator electronically as follows:
At low speed: Narrows the flow passage for the exhaust gas, resulting in increasing the
flow speed of the exhaust gas and running the turbine quickly and powerfully.
At high speed: Expands the flow passage for the exhaust gas, resulting in increasing the
mass flow of the exhaust gas and running the turbine more powerfully. -
-
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06-191914-01
T-MAP sensor
Booster pressure and
temperature
E-VGT turbocharger
Improves engine power
2. COMPONENTS
Engine ECU (D20DTR)
E-VGT duty controlAccelerator pedal position
sensor
Transfers driver's will to
accelerate to ECU
Atmospheric pressure, RPM
signal
HFM sensor
Improves the engine powerCoolant temperature sensor
Operates the VGT according
to engine warm-up
* 세부제어로직은 엔진제어편 참조
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07-51543-00
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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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 265 of 828
10-4
Glow plug control unit
(GCU)
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
Glow indicatorEngine ECU (D20DTR)
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10-71413-00
4) Operation
Glow plug is installed in the cylinder head. It enhances the cold starting performance and reduces
the exhaust gas during cold starting.
(1) Operation
Duty control area:
Between 5 and 100%
Frequency: 20 Hz
Duty ratio = (RMS voltage)²
(Battery voltage)² 1.
2.
3.
Pre-Glow: Step 1 ▶
If normal communication with the ECU is established 2 seconds after the power is supplied to the
IGN terminal from the battery, the GCU supplies the battery power to raise the temperature of the
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47009b008f008c0047008c0095008e00900095008c0047006c>CU before starting.
Pre-
heatingCoolant
temperature-30°C -25°C -20°C -10°C -5°C 0°C 20°C
Operating time
28 s 25 s 15 s 5 s 2 s 2 s 0 s
Operating
conditions- IGN: ON
- B+: below 15.2 VStop
conditions- Time-out
- IGN: OFF
- when engine cranking
If the input power (VB) is 11.5 V or less, the GCU supplies the battery power for arrival time
(T1).
If the input power (VB) is greater than 11.5 V, the GCU supplies the voltage of 11.5 V for arrival
time (T1). 1.
2.
- The time for pre-heating is controlled by the ECU.
The time for pre-heating by coolant temperature can vary slightly depending on e.g. other
vehicle operation elements.
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10-8
During cranking: Step 2 and step 3 ▶
Step 2: If the ECU receives the cranking signal after pre-heating (step 1), the GCU supplies the
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8c0047009b00960047005800530058005700570b450055>
Step 3: The GCU supplies the voltage of 5.1 V to keep the temperature at 1,000°C. 1.
2.
Under fixed temperature: The AQGS unit supplies power for 30 seconds (Step 1 + Step 3)
if no cranking signal is received after the step 1.
At cranking: The step 3 is started after the step 2. *
*
Post-glow: Step 4: ▶
The post-heating is for reducing HC/CO after the engine is started. If the time for post-heating
exceeds 180 sec., the GCU unit cuts off the power to each glow plug even if there is pre-heating
request from the engine ECU.
Post-
heatingOperating time
(approx.)-20°C -10°C 0°C 20°C 80°C
Operating time
(approx.)100 s 50 s 25 s 10 s 10 s
Emergency glow ▶
If no CAN signal is received for 4 seconds from the engine ECU after the IGN ON signal is input,
the GCU performs emergency preheat (Step 3) for 30 seconds.
P1 to P2: Pre glow
P3 to P4: Post glow