Page 302 of 1082

15-26
d. Bypass control for EGR cooler
1. Cooler temperature
<007e008f008c00950047009b008f008c0047008a00960096009300880095009b0047009b008c00940097008c00990088009b009c0099008c00470090009a00470089008c00930096009e0047005e00570b4500530047009b008f008c0047008c009f008f00
88009c009a009b0047008e0088009a00470090009a00470089>ypassed the EGR cooler.
2. Exhaust gas temperature
<007e008f008c00950047009b008f008c0047008c009f008f0088009c009a009b0047008e0088009a0047009b008c00940097008c00990088009b009c0099008c00470090009a00470089008c00930096009e0047005a005700570b4500530047009b008f00
8c0047008c009f008f0088009c009a009b0047008e0088009a> is bypassed the EGR cooler.
Otherwise, PM could be increased due to too low exhaust gas temperature.
e. Control elements for EGR system
Accelerator pedal (engine load) - Indicates the driver's intention and engine load. If the load goes up,
the EGR ratio is decreased.
T-MAP (boost pressure map stored in ECU) - Compensates the difference in boost pressure by
adjusting EGR ratio.
Engine rpm - Used as the signal for determining EGR operating range.
Coolant temperature - When the coolant temperature is low, NOx is decreased but PM could be
increased. So, to reduce PM, decrease EGR ratio when the coolant temperature is low.
Intake air mass and temperature - HFM sensor measures the intake air mass to calculate the actual
EGR volume. If the air mass is larger than programmed value in map, EGR ratio will be higher.
EGR position sensor - Detects the actual opening angle of EGR valve and performs feedback
function according to PWM control by ECU.
Wide band oxygen sensor - Detects the oxygen volume in exhaust gas to check if the EGR ratio is
proper.
Electronic throttle body - Keeps EGR ratio to optimized level by controlling the throttle body in EGR
operating range (decreasing pressure in intake manifold). -
-
-
-
-
-
-
-
Page 310 of 1082

15-34
Coolant temp.
sensor
(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
Refrigerant pres.
sensor
A/C compressor
ECU
D20DTF DSI 6 A/T
(ATF temp.)
Cooling fan module
HFM sensor
(Intake air
temperature)
Engine room
relay box
Page 332 of 1082

01-8
4) Basic Inspection
(1) Horn operation
Listen for the horn sound when pressing the horn pad on the steering wheel. -
(2) Brake operation
Check if there is any abnormal noise, unusually long braking distance, or uneven braking force. If the
brake warning lamp does not go out even after starting the engien or are flashing during driving,
have the brake system checked immediately.
Check the brake pipes and hoses for connection, oil leak, crack or interference after changing the
position of tires. When replacing the tires, check the brake disc for surface condition and wear.
Check the parking brake cable and brake operation. Shorten the checking interval if the parking
brake is used frequently. -
-
-
(3) Exhaust system
Be aware to any changes in sound or smell from the exhaust system. These may be caused by leak or
overheat. Have the exhaust system checked and repaired immediately.
Inspect the exhaust system including catalytic converter. Inspect all the components and body frame
near the exhaust system. -
-
(4) Tires
Unusual vibration of the steering wheel and seats or pulling to one side on the straight and level roads
may indicates the uneven tire inflation pressure or poor wheel balance. -
(5) Steering and suspension system
Inspect the front and rear suspension and the steering system for damage, looseness or missing
parts, signs of wear or lack of lubrication. Inspect the power steering line and the hoses for
connection, leak, crack and chafing. Inspect the drive axle boot and seals for damage, tear or leak.
Replace or repair the system if necessary. -
(6) Engine oil
Check the oil level when the engine is still warm and add the specified engine oil if necessary. -
(7) Coolant
Check the coolant level in the coolant reservoir, coolant conditions (contamination, foreign material),
and hoses for damage and leak. Replace or add the Ssangyong genuine coolant, if needed. -
(8) Engine drive belt
Check all drive belts on the engine for wear, crack and looseness. Retighten or replace the belt, if
needed. -
Page 427 of 1082

08-4
Problem Possible Cause Action
Coolant
level is too low
Coolant
temperature is
too high
2. INSPECTION
Leak from the radiator
Leak from the coolant auxiliary tank
Leak from the heater core -
-
-
Leak from the water inlet cap
Leak from the thermostat housing -
-Reconnect the hose or replace the
clamp
Change the hose -
- Leak from the coolant hose connections
Damaged coolant hose -
-
Change the gasket
Change the water pump -
- Leak from the water pump gasket
Leak from the water pump internal seal -
-
Tighten the bolts to the specified
torque
Change the cylinder head gasket -
- Incorrect tightening torque of the cylinder
head bolts
Damaged cylinder head gasket -
-Change the water inlet cap gasket
Change the thermostat sealing -
-
Coolant leakage (Coolant level is low)
Improper coolant mixture ratio
Kinked coolant hose -
-
-Add coolant
Check the coolant concentration
(Anti-freeze)
Repair or replace the hose -
-
-
Defective thermostat
Defective water pump
Defective radiator
Defective coolant auxiliary tank or tank
cap -
-
-
-Change the thermostat
Change the water pump
Change the radiator
Change the coolant auxiliary tank or
tank cap -
-
-
-Change the radiator
Change the coolant auxiliary tank
Change the heater -
-
-
Cracks on the cylinder block or
cylinder head
Clogged coolant passages in the
cylinder block or cylinder head -
-Change cylinder block or cylinder
head
Clean the coolant passage -
-
Clogged radiator core -
Replace the sensor or repair the
related wiring - Improper operation of cooling fan -Clean the radiator core -
Defective temperature sensor or faulty
wiring -Replace the cooling fan or repair the
related circuit -
Page 429 of 1082
08-6
1) Coolant Level Check
Park the vehicle on level ground and apply the parking brake. Stop the engine and wait until it is
cooled down. The coolant level should be between the MAX and MIN mark on the coolant reservoir.
If the coolant level is below the “MIN” mark, immediately add coolant. A.
B.
Coolant reservoir
MAX
MIN
Scalding hot coolant and steam could be blown out under pressure, which could cause serious
injury. Never remove the coolant reservoir cap when the engine and radiator are hot.
Avoid any direct contact of the coolant to the painted body of the vehicle. -
-
Page 430 of 1082
08-72112-01
2) Leak Test
Release the pressure in the system by
loosening the pressure cap of the coolant
reservoir slightly. Then, remove the pressure
cap completely. A.
Never open the cap until the coolant
temperature becomes under 90℃ to
prevent any burn.
Add the coolant so that the coolant level is
between MAX and MIN mark on the coolant
auxiliary tank.
Connect the tester to the tank filler and apply
pressure (1.4 bar).
Check all the coolant hoses, pipes and
connections for leaks when the pressure of
the tester drops, and replace or tighten, if
necessary. B.
C.
D.
3) Thermostat
Immerse the thermostat into the water. Heat the
water and check the valve opening temperature.
Valve opening
temperature90±2℃
Page 482 of 1082

15-170000-00
(2) Warm-up Control Function
Low voltage ▶
If low voltage is detected by the ECU, the idle speed increases up to 100 rpm selectively under the
driving mode until the ignition switch is turned off. Idle speed control ▶
The idle speed is controlled according to the fuel/air mixture when the engine load is changed, the
power steering wheel is turned to its end, the selector lever is in the "D" position and the A/C compresso
r
is in operation. It is also controlled according to the charge level during the purge control operation.
Ignition timing ▶
The idle speed is controlled according to the fuel/air mixture when the engine load is changed, The
<0090008e00950090009b009000960095004700880095008e0093008c0047008a0088009500470089008c00470099008c009b00880099008b008c008b0047009c00970047009b00960047005a005d020b00470096009900470088008b009d00880095008a00
8c008b0047009c00970047009b0096004700590057020b0047>to help idle speed control.
Air conditioner compressor operation ▶
The air conditioner control unit sends the air conditioner operation signal to the ECU to increase the
throttle valve opening amount in order to prevent reduction of the engine speed when the air conditioner
compressor is in operation at idling.
(3) Warm-up Control Operating Conditions
To make the catalytic converter reach a operating temperature, the ignition timing is retarded for about
20 seconds under the following conditions:
The coolant temperature is 15°C ~ 40°C when the engine is started.
The selector lever is in the "P" or "N" position. ▶
▶
Also, the idle speed increases to 1100 ~ 1500 rpm simultaneously by the idle speed control. However, as
soon as the selector lever is shifted to the D position, warming up control of the catalytic converter will be
inhibited. The information necessary to perform such control is as follows:
Coolant temperature
Engine rpm
Intake air mass
Recognizing idling status
Selector lever position ▶
▶
▶
▶
▶
Page 483 of 1082
15-18
6) Cooling Fan Control
(1) 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 (180W+120W) in G20DF engine. ECU
controls the electric cooling fans with three cooling fan relays to improve the engine torque and air
conditioning performance.
(2) Components
Refrigerant pressure
sensorCoolant temperature
sensorG20DF Engine
ECURelay box in engine
compartment
A/C compressorCooling fan moduleT-MAP sensor