1793-01
2) Input/Output Devices
3) Control Logic
The EGR system controls the EGR amount based on the map values shown below:
Main map value: Intake air volume
Auxiliary map value:
Compensation by the coolant temperature
Compensation by the atmospheric pressure: Altitude compensation
Compensation by the boost pressure deviation (the difference between the requested value and the
measured value of boost pressure)
Compensation by the engine load: During sudden acceleration
Compensation by the intake air temperature -
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The engine ECU calculates the EGR amount by adding main map value (intake air volume) and auxiliary
map value and directly drives the solenoid valve in the E-EGR to regulate the opening extent of the EGR
valve and sends the feedback to the potentiometer.
(1) Operating conditions
Atmospheric pressure: 0.92 bar or more
When there is no fault code related to EGR -
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(2) Shut off conditions
Abrupt acceleration: with engine speed of 2600 rpm or more
When the engine is idling for more than 1 minute
Vehicle speed: 100 km/h or more
Engine torque: 380 Nm or more -
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1. ENGINE DATA LIST
Data Unit Value
Coolant temperature
Intake air temperature
temperature or engine mode)
Idle speed rpmA/T
M/T
Engine load % 18~25%
Mass air flow kg/h 16 to 25 kg/h
Throttle position angle
Engine torque Nm varies by engine conditions
Injection time ms 3 to 5ms
Battery voltage V 13.5 V to 14.1 V
Accelerator pedal position 1 V 04. to 4.8V
Accelerator pedal position 2 V 0.2 to 2.4 V
Throttle position 1 V 0.3 to 4.6 V
Throttle position 2 V 0.3 to 4.6 V
Oxygen sensor mV 0 to 5 V
A/C compressor switch 1=ON / 0=OFF -
Full load 1=ON / 0=OFF -
Gear selection (A/T) 1=ON / 0=OFF -
Knocking control 1=ON / 0=OFF -
Brake switch 1=ON / 0=OFF -
Cruise control 1=ON / 0=OFF -
Pilot injection timing control
The pilot injection timing is determined as a function of the engine speed and of the total flow.
The elements are:
A first correction is made according to the air and coolant temperatures. This correction allows the
pilot injection timing to be adapted to the operating temperature of the engine.
A second correction is made according to the atmospheric pressure. This correction is used to adapt
the pilot injection timing as a function of the atmospheric pressure and therefore the altitude. -
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d. Fuel Control
1. Main Flow Control
The main flow represents the amount of fuel injected into the cylinder during the main injection. The pilot
flow represents the amount of fuel injected during the pilot injection.
The total fuel injected during 1 cycle (main flow + pilot flow) is determined in the following manner.
When the driver depress the pedal, it is his demand which is taken into account by the system in order
to determine the fuel injected.
When the driver release the pedal, the idle speed controller takes over to determine the minimum fuel
which must be injected into the cylinder to prevent the enigne from stalling.
It is therefore the greater of these 2 values which is retained by the system. This value is then compared
with the lower flow limit determined by the ESP system.
As soon as the injected fuel becomes lower than the flow limit determined by the ESP system, the
antagonistic torque (engine brake) transmitted to the drive wheels exceeds the adherence capacity of
the vehicle and there is therefore a risk of the drive wheels locking.
The system thus chooses the greater of these 2 values (main flow & pilot flow) in order to prevent any
loss of control of the vehicle during a sharp deceleration.
As soon as the injected fuel becomes higher than the fuel limit determined by the ASR trajectory control
system, the engine torque transmitted to the wheels exceeds the adhesion capacity of the vehicle and
there is a risk of the drive wheels skidding. The system therefore chooses the smaller of the two values
in order to avoid any loss of control of the vehicle during accelerations.
The anti-oscillation strategy makes it possible to compensate for fluctuations in engine speed during
transient conditions. This strategy leads to a fuel correction which is added to the total fuel of each
cylinder.
The main fuel is obtained by subtracting the pilot injection fuel from the total fuel.
A mapping determines the minimum fuel which can control an injector as a function of the rail pressure.
As soon as the main fuel falls below this value, the fuel demand changes to 0 because in any case the
injector is not capable of injecting the quantity demand. A switch makes it possible to change over from the supercharge fuel to the total fuel according to the
state of the engine.
Until the stating phase has finished, the system uses the supercharged fuel.
Once the engine changes to normal operation, the system uses the total fuel. -
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3. Idle Speed Controller
The idle speed controller consists of 2 principal modules:
The first module determines the required idle speed according to:
* The operating conditions of the engine (coolant temperature, gear engaged)
* Any activation of the electrical consumers (power steering, air conditioning, others)
* The battery voltage
* The presence of any faults liable to interface with the rail pressure control or the injection control. In
this case, increase the idle speed to prevent the engine from stalling.
The second module is responsible for providing closed loop control of the engine's idle speed by
adapting the minimum fuel according to the difference between the required idle speed and the
engine speed. -
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4. Flow Limitation
The flow limitation strategy is based on the following strategies:
The flow limitation depending on the filling of the engine with air is determined according to the
engine speed and the air flow. This limitation allows smoke emissions to be reduced during
stabilized running.
The flow limitation depending on the atmospheric pressure is determined according to the engine
speed and the atmospheric pressure. It allows smoke emissions to be reduced when driving at
altitude.
The full load flow curve is determined according to the gear engaged and the engine speed. It
allows the maximum torque delivered by the engine to be limited.
A performance limitation is introduced if faults liable to upset the rail pressure control or the
injection control are detected by the system. In this case, and depending on the gravity of the fault,
the system activates: -
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Reduced fuel logic 1: Guarantees 75 % of the performance without limiting the engine speed.
Reduced fuel logic 2: Guarantees 50 % of the performance with the engine speed limited to 3,000 rpm.
Reduce fuel logic 3: Limits the engine speed to 2,000 rpm.
The system chooses the lowest of all values.
A correction depending on the coolant temperature is added to the flow limitation. This correction makes
it possible to reduce the mechanical stresses while the engine is warming up. The correction is
determined according to the coolant temperature, the engine speed and the time which has passed
since starting.
Superchager Flow Demand
The supercharge flow is calculated according to the engine speed and the coolant temperature. A
correction depending on the air temperature and the atmospheric pressure is made in order to increase
the supercharge flow during cold starts. It is possible to alter the supercharge flow value by adding a flow
offset with the aid of the diagnostic tool.
Coolant temp.
sensor
Refrigerant pres.
sensor
A/C compressor
ECU
D20DTFDSI 6 A/T
(ATF temp.)
Cooling fan module
HFM sensor
(Intake air
temperature)
Engine room
relay box
(8) Cooling fan control
a. Overview of cooling fan and A/C compressor
The cooling system maintains the engine temperature at an efficient level during all engine operating
conditions. The water pump draws the coolant from the radiator. The coolant then circulates through
water jackets in the engine block, the intake manifold, and the cylinder head. When the coolant reaches
the operating temperature of the thermostat, the thermostat opens. The coolant then goes back to the
radiator where it cools. The heat from automatic transaxle is also cooled down through the radiator by
circulating the oil through the oil pump.
There are two cooling fans (200W+150W) in D20DTF engine. ECU controls the electric cooling fans
with three cooling fan relays to improve the engine torque and air conditioning performance.
For details about A/C compressor and refrigerant pressure sensor, refer to Chapter "Air Conditioning
System" in "Body" section.
b. Components
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3) General Instructions
Before lifting up the vehicle with a lift, correctly support the lifting points.
When using a jack, park the vehicle on a level ground and place the wheel chocks under the tires.
Position the jack under the frame and lift up the vehicle and then support with chassis stand before
service work.
Make sure to disconnect the negative (-) cable from the battery to prevent any damage to electric
systems.
If you have to work on vehicle, cover the seats and floor with protection covers to avoid any
damage and contamination.
Brake fluid and anti-freeze can damage the painted surface of body. So carefully handle them
during service work.
To improve the efficiency of service work, use only recommended and specified tools.
Use only Ssangyong genuine spare parts.
Never reuse the cotter pin, gasket, O-ring, oil seal, lock washer and self-locking nut. Replace them
with new ones. If reused, normal functions cannot be maintained.
Store the disassembled parts as a set based on disassembly order and unit.
Pay particular attention not to miss or mix the fasteners.
If necessary, especially for inspection, clean the removed parts completely.
Apply the oil or grease on the running and sliding surfeces before installation. Use the specified
sealant and gasket to prevent leakage if necessary.
Tighten the fasteners to the specified tightening torque.
As a final stage of service work, check if the serviced system is working properly and the problem
has been eliminated clearly. (1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14) Remove the engine and transaxle as a set.
Manual transaxle: Transaxle can be separated after removing the front module (sub frame, engine
and transaxle).
Automatic transaxle: Transaxle can be separated after removing the sub frame. -
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2) Equipment
Korando is FF (Front Engine Front Drive) type vehicle, and engine and powertrain system are
integrated into a module. Therefore, 2-post lift and general equipment are necessary when working
on the engine and transmission.
Major equipment: Engine and transmission jack, Engine stand, Engine crane, Transmission jack,
Engine hanger -
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5) Guidelines on Engine Service
(1) Cautions before service works
Make sure to disconnect the negative (-) cable from the battery to prevent any damage to electric
systems.
Make sure to clean the working area and to prepare the necessary tools before service works.
Always place the ignition switch to OFF position if not required. Otherwise, there could be unexpected
damage to electric devices or personal injuries due to short-circuit.
To prevent the foreign material from entering into the fuel injection system, completely seal the inlets o
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HP pump, fuel hoses and high pressure pipes.
To remoev the engine, use the dedicated equipments such as engine jack, transmission jack, engine
stand and engine crane. -
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(2) Engine and accessories
When disassembling the engine, related parts (bolts, gaskets, etc.) should be stored as a set.
Clean the components completely with engine oil before assembling if needed.
Fully drain the engine oil, coolant and fuel from the vehicle and seal the inlets with the plugs before
removing the engine.
All the interference should be eliminated before removing the engine. -
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- To prevent the personal injuries and vehicle damages that can be caused by mistakes during service
and to provide the optimized performance and safety after service works, the service technicials must
keep the basic cautions and service guidelines below. These could be easily forgotten during service
works.
Engine has a lot of precise components. The specified tightening torque and correct procedures should
be kept during service works. And, the working area is always clean and well prepared.
To prevent any damage to electric systems, make sure to disconnect the negative (-) cable from the
battery and place the ignition switch to OFF position before servicing.
Use only the specified parts with same ratings when replacing the electric devices. Check the
grounds and connections for looseness. -
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(3) Electric devices
Extraordinary care should be taken when servicing the electric systems. Currently, the engine uses a lot
of electric devices. Short circuit and poor contact may cause the low engine performance, incomplete
combustion and other abnormalities.
When working with the fuel or oil systems in enclosed area, always keep the working area well-
ventilated and never allow anybody to smoke.
Gaskets and seals on the fuel and oil systems should be replaced with new ones. All bolts and nuts
should be tightened as specified.
Make sure to check the connections for leak after installation. -
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(4) Fuel and lubrication system
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3. STANDARD BOLTS SPECIFICATIONS
Metric bolt strength is embossed on the head of each bolt. The strength of bolt can be classified as
4T, 7T, 8.8T, 10.9T, 11T and 12.9T in general.
Observe standard tightening torque during bolt tightening works and can adjust torque to be proper
within 15 % if necessary. Try not to over max. allowable tightening torque if not required to do so.
Determine extra proper tightening torque if tightens with washer or packing.
If tightens bolts on the below materials, be sure to determine the proper torque. 1)
2)
3)
4)
Aluminum alloy: Tighten to 80 % of above torque table.
Plastics: Tighten to 20 % of above torque table. -
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