Page 191 of 600
Water pump and pipe
6. LAYOUT OF COOLING SYSTEM
From heaterThermostat (internal)
Reservoir
(coolant inlet hose)
Radiator
Radiator
Return hose
Coolant reservoir tank
From
heater
Radiator
Reservoir
(coolant inlet hose)
EEGR cooler
EGR cooler
Coolant port
Water pump
Page 269 of 600
0000-00
7. CODING AND INITIALIZATION
1) Engine Variant Coding
Unit Selection Description Remarks
PTC auxilary heater NO For PTC auxilary heater
equipped vehicle, select
"YES".-
YES YES
Glow plug Relay (K-line) Select "AQGS". -
AQGS (CAN) AQGS (CAN)
Transmission 6-speed M/T Select the appropriate system. Select
5-speed A/T (DC 5 AT) Select
6-speed A/T (DSI 6 AT) Select
Pressure sensor for
A/C refrigerantNO Select the appropriate system. -
Type Pressure sensor
for A/C
refrigerant
Immobilizer NO Select "YES" if the vehicle has
immobilizer.-
YES YES
Vehicle speed input
typeCAN Select "CAN" if the vehicle has
ABS or ESPCAN
WIRE -
Fan 2 relays Select "PWM". -
PWM fan PWM fan
Auto cruise NO Select "YES" if the vehicle has
cruise contro.-
YES YES
G-sensor NO 2WD ABS & Non-ABS: NO
4WD ABS & ESP: YESSelect
YES Select
Page 317 of 600
2210-01
1. SPECIFICATION
Description Specification
Fuel Diesel
Fuel filterType Fuel heater + priming pump + water
separator integrated type
Filter type Changeable filter element type
Water accumulating capacity 200 cc
Heater capacity 250W 13.5V
Injector System pressure 1800 bar
High pressure fuel
pumpType Eccentric cam/Plunger type
Operating type Gear driven type
Normal operating temperature
Operating pressure 1800 bar
Operating temperature
Low pressure fuel
pumpType Vane type
Gear ratio (pump/engine) 0.5 : 1
Pressure 6 bar
Fuel tankCapacity 75 L
Material Steel
Fuel sender Single sender type
Change interval EU every 40,000 km
GEN every 45,000 km
Water separation
intervalEU every 20,000 km
GEN every 15,000 km
Page 334 of 600

(2) Di engine and its expected problems and remedies can be caused by
water in fuel
System supplement against paraffin separation
In case of Diesel fuel, paraffin, one of the elements, can be separated from fuel during winter and then
can stick on the fuel filter blocking fuel flow and causing difficult starting finally. Oil companies supply
summer fuel and winter fuel by differentiating mixing ratio of kerosene and other elements by region and
season. However, above phenomenon can be happened if stations have poor facilities or sell improper
fuel for the season. In case of DI engine, purity of fuel is very important factor to keep internal
preciseness of HP pump and injector.
Accordingly, more dense mesh than conventional fuel filter is used. To prevent fuel filter internal clogging
due to paraffin separation, SYMC is using fuel line that high pressure and temperature fuel injected by
injector returns through fuel filter to have an effect of built-in heater (see fuel system).
System supplement and remedy against water in fuel
As mentioned above, some gas stations supply fuel with excessive than specified water. In the
conventional IDI engine, excessive water in the fuel only causes dropping engine power or engine
hunting. However, fuel system in the DI engine consists of precise components so water in the fuel can
cause malfunctions of HP pump due to poor lubrication of pump caused by poor coating film during high
speed pumping and bacterization (under long period parking). To prevent problems can be caused by
excessive water in fuel, water separator is installed inside of fuel filter. When fuel is passing filter, water
that has relatively bigger specific gravity is accumulated on the bottom of the filter.
Water drain from water separator
If water in the separator on the fuel filter exceeds a certain level, it will be supplied to HP pump with fuel,
so the engine ECU turns on warning lamp on the meter cluster and buzzer if water level is higher than a
certain level.
Due to engine layout, a customer cannot easily drain water from fuel filter directly, so if a customer
checks in to change engine oil, be sure to perform water drain from fuel filter.
Water
separator
To separate the water from the fuel filter,
remove the fuel filter assembly first.
Page 338 of 600

2) Fuel System Flow Diagram
The fuel from the fuel tank is supplied to the fuel heater of fuel filter/priming pump and then low pressure
generated by the low pressure pump (built into HP pump) is transmitted to the HP pump.
The fuel pressure at the HP pump is controlled by the IMV valve, and the maximum allowed pressure is
1,800 bar. The compressed fuel at the fuel pump is delivered to the rail, and injected by the injectors
according to the injection signals. The injection method is the same with the conventional method; Fuel
return by backleak which operates the needle valve.
The major difference is that the fuel return line is connected to the fuel filter inlet port, not the HP pump
venturi.
The pressure from the high pressure pump is increased to 1,800 bar from 1,600 bar, and the pump is now
installed to the cylinder head (cylinder block for previous model). The fuel pressure is generated by the
operation of intake camshaft and gears. The specifications for the IMV valve and the fuel temperature
sensor are not changed.
Page 379 of 600

2. INSPECTION
Problem Possible Cause Action
Coolant level is
too low- Leak from the radiator
- Leak from the coolant auxiliary tank
- Leak from the heater core- Change the radiator
- Change the coolant auxiliary tank
- Change the heater
- Leak from the coolant hose
connections
- Damaged coolant hose- Reconnect the hose or replace
the clamp
- Change the hose
- Leak from the water pump gasket
- Leak from the water pump internal
seal- Change the gasket
- Change the water pump
- Leak from the water inlet cap
- Leak from the thermostat housing- Change the water inlet cap
gasket
- Change the thermostat sealing
- Incorrect tightening torque of the
cylinder head bolts
- Damaged cylinder head gasket- Tighten the bolts to the specified
torque
- Change the cylinder head gasket
Coolant
temperature is
too high- 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
- 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 - Clean the radiator core
- Improper operation of cooling fan - Replace the cooling fan or repair
the related circuit
- Defective temperature sensor or
faulty wiring- Replace the sensor or repair the
related wiring
Coolant
temperature is
too low- Thermostat is stuck open - Change the thermostat
- Improper operation of cooling fan - Replace the cooling fan or repair
the related circuit
- Defective temperature sensor or
faulty wiring- Replace the sensor or repair the
related wiring
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)
Page 446 of 600
(3) Components for ECU Output
CAN
E-EGR cooler
bypass valve
- Instrument cluster
- TCU
- Self diagnosis
PTC heaterCooling fan
E-EGR valve
Variable swirl
valveE-VGT actuatorIMV valve
A/C compressorInjectorThrottle position
sensor
- Glow plug unit
- ABS & ESP unit
- GCU