2012 SSANGYONG KORANDO engine

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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

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d. Cooling fan and A/C compressor control
Conditions for cooling fan ▶
The cooling fan module controls the cooling fan relay, high speed relay and low speed relay. The cooling
fan is controlled by the series and parallel circuits.
A/C switch Cooling fanCoolant temperature Refrigerant pressure
A/C
compressor
OFF OFF Coolant temp. < 90℃-
LO 90℃ ≤ Coolant temp.
< 105℃-
HI105℃ ≤ Coolant temp-
ONLO
Coolant temp. < 105℃Refrigerant pressure <
18 bar
ON HI18 bar ≤ Refrigerant
pressure
HI105℃ ≤ Coolant temp.
< 115℃-
HI115℃ ≤ Coolant temp. - OFF (cut)
A/C compressor OFF conditions ▶
Coolant temperature: below -20℃ or over
115℃
Approx. 4 seconds after starting the engine
Engine rpm: below 650 rpm or over 4500 rpm
When abrupt acceleration
Refrigerant pressure:
* OFF below 2.0 kg/㎠, then ON over 2.4 kg/㎠
* OFF over 30 kg/㎠, then ON below 21.4 kg/㎠ -
-
-
-
-
The output voltage from refrigerant pressure sensor is 1.7 V to 3.5 V when the refrigerant pressure is 10
to 24 kgf/㎠ with A/C "ON".Output voltage according to refrigerant pressure ▶
Cooling fan control according to ATF temperature ▶
ATF temperature Cooling fan Remark
Over 100˚CHigh speed -

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HFM
(Intake air temp.)Coolant temp.
sensor
(9) PTC heater control
a. Overview
The supplementary electrical heater is installed in DI engine equipped vehicle as a basic equipment. The
PTC system is operated according to two temperature values measured at the coolant temperature
sensor and HFM sensor. This device is mounted in the heater air outlet and increase the temperature of
air to the passenger compartment. Because PTC system is heated by electrical power, high capacity
alternator is required. PTC does not operate during engine cranking, while the battery voltage is lower
than 11 V or during preheating process of glow plugs.
b. Components
PTC heater
D20DTF
ECU
Engine room relay box
A: PTC 1 (changeable)
B: PTC 2,3 (not changeable)

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d. Control conditions
Operation Operating condition PTC Heater
HI
(PTC2)- Coolant temperature < 15℃
PTC HI ON
LO
(PTC1)- Coolant temperature 15℃ ≤ 65℃, intake air
temperature ≤ -10℃
- Coolant temperature 15℃ < 65 to 60℃, intake air
temperature <-10℃ to 0℃
- Coolant temperature 15℃ ≤ 60℃, intake air
temperature ≤ 0℃ to 5℃PTC LO ON
Stop- A/C blower switch OFF
- Defective ambient air temperature sensor
(including open or short circuit)
- Engine cranking
- Low battery voltage (below 11V)
- During pre-glow process (glow indicator ON)
Operation diagram for PTC heater LO (step 2) ▶

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Meter clusterImmobilizer
antenna
(10) Immobilizer control
a. Overview
The Immobilizer System provides an additional theft deterrent to the vehicle in which it is installed and
prevents it from being started by unauthorized persons. The transponder integrated in the key and the
engine control unit have the same code. When the ignition key with the integrated transponder is turned
to the ON position, the ECU (Engine Control Unit) checks the crypto code of the key and, if correct,
allows the vehicle to start the engine.
For details, refer to Chapter "BCM".
b. Components
Basic components (ignition key system) ▶
Immobilizer key
Start motor
BCM
ECU
D20DTF

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Key approval process ▶
When turning the ignition switch to ON position, the power is supplied to BCM and ECU. ECU
communicate with the immobilizer key to check if it is valid crypto code. If it is valid, ECU start to control
the engine when turning the ignition switch to START position.
The system has 10 seconds of valid time-out period. If the engine does not start in this period, the key
approval process should be done again.

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Key approval process in Smart key system equipped vehicle
The key approval consists of two processes; immobilizer key approval and Smart key
approval. ▶
Immobilizer key approval: When inserting the Smart key into Smart key slot, the power is supplied to the
key slot. SKM communicate with the Smart key in key slot to check if it has valid crypto code. If it is valid,
ECU start to control the engine when pressing the Engine Start/Stop button. The system has 10
seconds of valid time-out period. If the engine does not start in this period, the key approval process
should be done again.
Smart key approval: When pressing the Engine Start/Stop button or depressing the brake pedal without
Smart key inserted into the key slot, SKM communicate with the Smart key to check if it has valid crypto
code. If it is valid, the engine can be started.

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Front temp. sensor
(11) CDPF control
a. Overview
As the solution for environmental regulations and PM Particle Material) of diesel engine, the low emission
vehicle is getting popular. This vehicle is equipped with an extra filter to collect the soot and burn it again
so that the amount of PM in the exhaust gas passed through the DOC (Diesel Oxidation Catalyst) is
reduced. The CDPF (Catalyst & Diesel Particulate Filter) is an integrated filter including DOC (Diesel
Oxidation Catalyst) and DPF (Diesel Particulate Filter).
For details, refer to Chapter "CDPF".
b. Components
Rear temp. sensorCDPF (DOC+DPF)
Throttle valveD20DTF ECUDifferential pres.
sensorOxygen sensor