Page 370 of 600
1914-01
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-upT-MAP sensor
Booster pressure and
temperature
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1543-00
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
Page 384 of 600
1520-00
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 397 of 600
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)
Glow plug control unit
(GCU)
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1413-00
Voltage pattern in actual stepGCU PWM control
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.
Duty control area:
Between 5 and 100%
Frequency: 20 Hz
1.
2.
3.
(1) Temperature/Current Properties of GCU
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. 1.
2.
3.
Frequency:
20~33Hz
PWM control duty
ratio
- 1st step: 100%
- 2nd step: 35%
- 3rd step: 23%
This describes the voltage supplying types to glow plugs. This shows the supplying voltage and
time by GCU in each step. The 3rd
step is the period to keep the
temperature.
(2) Operation Type of GCU
Page 401 of 600
(3) Operation
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 glow plug
- The time for pre-heating is controlled by the ECU.
Input power VB(V) Arrival time T1(s)
68.27
75.8
84.1
93.15
10 2.4
11 1.95
1.9
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). -
-
The time for pre-heating by coolant temperature can vary slightly depending on e.g. other vehicle
operation elements.
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1413-00
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 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.
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.
Post-heatingOperating time
(approx.)
Operating time
(approx.)100 s 50 s 25 s 10 s 10 s
Page 411 of 600
8510-23
2. CONFIGURATION
1) Circuit Diagram
The engine ECU detects the operating conditions of cruise control system, and monitors the braking
performance, vehicle speed, road conditions and ESP system operation. If the engine ECU determines
that there are not any problem to drive in cruise control mode, the vehicle can be operated by cruise
switch signals (decelerating, accelerating, cruising).