2012 SSANGYONG NEW REXTON engine

Excessive overload of CDPF (warning lamp illuminated)
If the vehicle is driven at a speed of 5 to 10 km/h for an extended period of time, the soot
accumulated in the CDPF cannot be burned as the CDPF cannot reach the regeneration
temperature. Then, an excessive amount of soot can be accumulated in the CDPF.
This case is much worse than the simple over-load of the CDPF. To inform this to the driver, the
engine warning lamp comes on and the engine power is decreased to protect the system.
To solve this problem, blow soot between the engine and exhaust system several times and erase
the related DTC. Then, check if the same DTC is regenerated again. If so, check the DTC related to
the differential pressure sensor. 1.
2.
3.
Illuminating

Differential pressure
sensor
Calculates the amount of
PM collected by reading the
pressure difference between
before and after the CDPF.Engine ECU
DCM 3.7
Post-injectionThrottle
valve
Regulates the rate of air
intake.
CDPF
DOC+DPFFront temperature
sensor
Protects the turbocharger.Rear temperature sensor
Measures the temperature
of fuel combustion.
2. COMPONENT
For details, refer to section "Engine Control". *

4. POST-INJECTION AND AIR MASS CONTROL
A DPS (Differential Pressure Sensor) measures the pressure difference between before and after the
CDPF and detects whether the soot is collected in the CDPF or not. If PM is collected in the CDPF (In
this case the pressure difference between before and after the CDPF exceeds the specified value.
Normally, the system sends the signal when the driving distance becomes approx. 600 to 1,200 km), the
temperature of exhaust gas is increased and the post-injection is started for regeneration. The amount of
fuel post-injection is controlled by the exhaust gas temperature measured by the rear temperature
increase the regeneration temperature. Otherwise, the fuel injection amount is decreased or the fuel is
not injected.
When the engine is running with low load, the intake air amount is also controlled as well as fuel injection
amount. This function is used to increaser the combustion temperature by increasing the amount of fuel
post-injection with the lowest air amount within the specified control logic.

2412-02
Front temperature sensor
Measures the temperature of
exhaust gas.
This sensor is located at the rear
side of exhaust manifold and
monitors the temperature of
combusted gas to prevent the
exhaust system from overheating.
When the temperature gets higher,
this sensor cuts off the fuel delivery
and controls the EGR to lower the
temperature.Rear temperature sensor
Measure the outlet
temperature of DOC.
This sensor is located at the
rear side of DOC and
monitors the overheating of
CDPF and post injection
volume.
Engine ECU (D20DTR)
Differential pressure sensor
Measures the difference between
inlet and outlet pressures of CDPF.
If the difference is higher than the
specified value when collecting the
PM, this makes the post injection for
forced recycling of PM.
T-MAP sensorIntake air
mass
Measures
the
excessive
amount of
PM.
Boos
t
pressure
/
temperature
Injector (C31)
Controls the post injection.
Electric throttle body
Controls the intake air mass.
HFM sensor
Wide band
oxygen senso
r

Collecting PM
The engine ECU detects the
amount of PM collected by the
information from the
temperature sensors and
differential pressure sensor.
When the soot is accumulated,
the engine ECU performs post-
injection to increase the
exhaust gas temperature and
burns the collected PM at
Oxidation (DOC)
When the exhaust gas enters
into the CDPF assembly, its
CO, HC and PM are reduced
by the redox reaction of the
DOC. The remaining PM is
filtered and collected in CDPF,
and the temperature of the
exhaust gas is increased to
5. OPERATING PROCESS
[Configuration and principle of operation]
The exhaust gas
passed through the
exhaust manifold
enters into the CDPF
assembly (at approx

4) Fuel Injection During CDPF Regeneration
Post injection
exhaust gas. The post injection does not make the actual output. The post injection activates the fuel by
injecting the fuel to the incompletely combusted gas after primary combustion. Through the process, the
PM and smoke in the exhaust gas could be reduced. There are totally 7 injections as shown in the
figure. However, all of 7 injections are not performed during driving because it decreases the fuel
economy. Totally 5 injections can be performed in one cycle. The injection method in D20DTR engine has three steps;
Pilot injection, Main injection, Post injection

7. CAUTIONS
1) Designated Engine Oil for CDPF (Low Ash Oil)
Need to use the designated engine oil for CDPF 1.
The smoke from the vehicle may generate the particle material in the ambient air. CDPF is the
device to reduce the smoke by collecting and recycling it. To ensure the performance of CDPF,
the designated engine oil should be used.
The smoke including combusted sulfur in fuel cannot be recycled in CDPF. This smoke
generates the ash, resulting in clogging the filter. -
-
Advantages when using the designated engine oil for CDPF 2.
Reduces the amount of ash
Improves the fuel economy and reduces the CO2
Increases the life span of engine oil
Available for all engines (diesel and gasoline) -
-
-
-
Problems when using non-designated engine oil for CDPF 3.
Decreases the life span of engine oil due to accumulated ash in DPF (around 30%)
Decreases the fuel economy due to friction resistance, exhaust gas resistance and frequent
recycling process of DPF -
-
The fuel containing high sulfur may cause the same problems.
2) Do Not Use the Fuel Containing High Sulfur
Producing white smoke during recycling 1.
The sulfur in exhaust gas is changed to sulfate gas during exhaust process. This sulfate gas is
shown as white smoke. -
Producing odor during recycling 2.
The sulfur after oxidation may produce the odor. -
Accumulation of ash 3.
The sulfur accumulated in DPF cannot be recycled. It reduces the life span of DPF. -
3) White Smoke
The white smoke can be generated when the exhaust gas is recycled in DPF. There are two reasons as
below.
Saturated vapor
Sulfate -
-

0000-00
1. ENGINE DATA LIST
Data Unit Value
Coolant temperature
Intake air temperature
temperature or engine mode)
Idle speed rpm
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 0.4. 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 -