differential SSANGYONG NEW REXTON 2012 User Guide

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

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3) PM Regeneration of DPF
The differential pressure sensor installed in the DPF measures the pressure values of inlet and outlet of
CDPF. And the amount of the PM collected in the filter is calculated based on the exhaust temperature,
intake air mass flow, booster pressure, etc.
The regeneration is started when the amount of the collected PM is 28 g or more.
When the amount of the collected PM is not enough: The DPF works as a filter. 1.
When enough amount of PM is collected: The ECU commands post-injection and increase the exhaust
gas temperature to start regeneration. 2.

Glow plug
Differential pressure
sensor
Camshaft position
sensor
1. MAJOR COMPONENTS
Rear EGT sensorOxygen sensor
Front EGT sensor
HFM (air mass/
temperature)Injector (C3I)Variable swirl valve
actuator
IMV

0000-00
Fuel rail pressure
sensor
(2) Components for ECU Input
CAN
- ABS & ESP
- GCU
- Instrument
cluster
- TCU
- STICSSwirl valve
position sensor
Differential
pressure sensorE-EGR valve
position sensorCamshaft position
sensorCoolant
temperature
sensor
Exhaust gas
temperature
sensorHFM sensorOxygen sensorT-MAP sensor
Crankshaft
position sensorAccelerator pedal
sensorThrottle position
sensorKnock sensor
-Auto cruise switch
- Rear right wheel
speed (without ABS)
- Refrigerant pressure
sensor
- Clutch pedal signal
- Blower switch signal
- Brake pedal signal
Water sensor

(15) 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
Oxygen
sensorFront
EGT sensorCDPF
(DOC + DPF)Rear
EGT sensor
Differential pressure
sensorD20DTR ECUElectric throttle body

Diff. pres. sensor: Measure
pressure between front
side and rear side of CDPF
ECU (DCM 3.7)
Injector: Control post
injection
D. Operation process
When the differential pressure sensor detects the pressure difference between the front and the rear
side of CDPF, the sensor sends signal indicating the soot is accumulated and the post injection is
performed to raise the temperature of exhaust gas. The amount of fuel injected is determined according
to the temperature of exhaust gas detected by the rear temperature sensor. If the temperature is below
low load range, the amount of post injection and the amount of intake air are controlled. It is to raise the
temperature by increasing the amount of fuel while decreasing the amount of intake air.
Front EGT sensor:
Measure DOC temp.
Rear EGT sensor: Measure
DPF temp.
Electronic throttle
body: Control intake
air mass
T-MAP sensor
Intake air
mass
Exceed PM
limitBooster
pressure/
temperaturePost injection
Control intake
air mass

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1. OVERVIEW FOR CDPF (EURO IV)
1) General Description
The CDPF (Catalyst & Diesel Particulate Filter) was installed to the Rexton II D27DTP engine
previously. However, it is now installed to the all 2009 DI engine models, except the
Actyon
Sports. The DI engine types installed to Rexton are D27DTP, D27DT and D20DT, and their CDPF,
related sensor and operation logic are the same.
This section describes the CDPF system (based on Euro IV) which is installed to the Rexton II
D27DTP engine (older model).
2) Compatibility of CDPF System by Vehicle Model
Rexton II: Same CDPF system for D27DTP and D27DT engines (including its components)
Kyron & Actyon: Same CDPF system for D27DT and D20DT engines (including its components)
The CDPF assemblies installed to the Euro IV D27DTP Rexton II and 2009 Rexton II are
different in their mounting layout, but their front/rear exhaust temperature sensors and
differential pressure sensors are same. -
3) System Met with Euro IV Regulations
E-EGR valve
EGR cooler
Engine ECU (Ver. 3.2)
HFM sensor
C3I injector
Electronic throttle valve (body)
Other engine mounting components -
-
-
-
-
-
-
For details about the modified components and system related to the Euro IV regulations, refer to
the 2008 Rodius engine service manual.

3) Post Injection and Air Mass Control
When the differential pressure sensor detects the pressure difference between the front and the
rear side of CDPF, the sensor sends signal indicating the soot is acumulated and the post
injection is performed to raise the temperature of exhaust gas. The amount of fuel injected is
determined according to the temperature of exhaust gas detected by the rear temperature sensor.
If the temperature is below
the amount of fuel injected is increased to raise the
temperature. If the temperature is over
the amount of fuel injected is decreased or not
controlled.
When the engine is running in low load range, the amount of post injection and the amount of
intake air are controlled. It is to raise the temperature by increasing the amount of fuel while
decreasing the amount of intake air.
2) Sytem Composition for Soot Combustion
When the engine is running in low load range, the temperature of exhaust gas is decreased as the
amount of fuel supplied is decreased. To burn the soot filtered in the CDPF, the control system
should be installed to check the operating range and increase the temperature of exhaust gas by
controlling the amount of fuel supplied and intake air.
Two temperature sensors and one differential pressure sensor monitor the CDPF's operating
range. According to these sensors' information, the throttle flap decreases the intake air entered
to the throttle body. Also, the fuel injection pattern is added to increase the temperature of
exhaust gas for soot combustion.
There are three fuel injection patterns (pilot injection, pre-injection and main injection). As the
CDPF is installed, the post injection pattern is added.

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Front temperature sensor
(Measuring the temperature of
exhaust gas passed through
exhaust manifold)
Differrential pressure sensor (Front
pressure port) Differrential pressure sensor (Rear
pressure port) Rear temperature sensor
(Measuring the temperature of exhaust gas
passed through DOC)
The exhaust gas enters
into CDPF assembly after
passing through the
exhaust manifold.
(Normal temperature of
exhaust gas: approx. The engine ECU detects
the amount of particulate
material colected by the
information from
temperature sensors and
differential pressure snesor.
When the soot is
accumulated, the pressure
difference between the
front and the rear side
occurs. Then, the engine
ECU performs the post
injection to raise the
exhaust gas temperature
and burn the collected soot
at approx. When the exhaust gas
enters into the CDP
F
assembly, its CO, HC and
particulate material are
reduced as it is oxidized in
DOC. The remaining
particulate material is
filtered and collected in
DPF and the temperature
of exhaust gas is
increased to approx. 450
~