Page 230 of 600
2) Fuel Injection During CDPF Regeneration
3) Warning Lamp Related To CDPF
CDPF regeneration process (warning lamp NOT illuminated)
The CDPF system enters the regeneration mode when the
driving distance becomes approx. 600 to 1,200 km (may
differ by the driving condition and driving style). Then, the
engine ECU performs the CDPF regeneration operation.
However, the driver is not in-formed with this operation by an
y
engine warning lamp or vehicle signal, so he/she may not
detect this operation. The control logic at the post-injection
dur-ing the regeneration process is to increase the fuel
injection volume and control the intake air volume (by the
throttle body) in order to increase the tem-perature of the
exhaust gas. The driver may not feel any particular difference
from the vehicle.
No illumination
Page 427 of 600

2412-02
The CDPF system enters the regeneration mode
when the driving distance becomes approx. 600
to 1,200 km (may differ by the driving condition
and driving style). Then, the engine ECU
performs the CDPF regeneration operation.
However, the driver is not informed with this
operation by any engine warning lamp or vehicle
signal, so he/she may not detect this operation.
The control logic at the post-injection dur-ing the
regeneration process is to increase the fuel
injection volume and control the intake air volume
(by the throttle body) in order to increase the
temperature of the exhaust gas. The driver may
not feel any particular difference from the vehicle.
Overload of CDPF (warning lamp blinking)
(3) Warning Lamp Related to CDPF
CDPF regeneration process (warning lamp NOT illuminated)
If the CDPF cannot reach the regeneration temperature due to low speed driving or other reason
during the regeneration process, the soot is continuously accumulated in the CDPF. When this
condition continues and the CDPF is overloaded with soot, the engine warning lamp blinks to inform
this situation to the driver.
In order to solve this problem, drive the vehicle at a speed of approx. 80 km/h for 15 to 20 minutes to
perform the CDPF regeneration process.
If the engine warning lamp on the instrument cluster blinks, the CDPF is overloaded. In this case,
perform the step 2. 1.
2.
3.
Turned off
Blinking
Page 447 of 600

0000-00
2) ECU Control
(1) Function
a. ECU Function
ECU receives and analyzes signals from various sensors and then modifies those signals into
permissible voltage levels and analyzes to control respective actuators.
ECU microprocessor calculates injection period and injection timing proper for engine piston speed and
crankshaft angle based on input data and stored specific map to control the engine power and emission
gas.
Output signal of the ECU microprocessor drives pressure control valve to control the rail pressure and
activates injector solenoid valve to control the fuel injection period and injection timing; so controls
various actuators in response to engine changes. Auxiliary function of ECU has adopted to reduce
emission gas, improve fuel economy and enhance safety, comforts and conveniences. For example,
there are EGR, booster pressure control, autocruise (export only) and immobilizer and adopted CAN
communication to exchange data among electrical systems (automatic T/M and brake system) in the
vehicle fluently. And Scanner can be used to diagnose vehicle status and defectives.
water and electromagnetism and there should be no mechanical shocks.
To control the fuel volume precisely under repeated injections, high current should be applied instantly
so there is injector drive circuit in the ECU to generate necessary current during injector drive stages.
Current control circuit divides current applying time (injection time) into full-in-current-phase and hold-
current-phase and then the injectors should work very correctly under every working condition.
b. Control Function
Controls by operating stages
To make optimum combustion under every operating stage, ECU should calculate proper injection
volume in each stage by considering various factors.
Starting injection volume control
During initial starting, injecting fuel volume will be calculated by function of temperature and engine
cranking speed. Starting injection continues from when the ignition switch is turned to ignition
position to till the engine reaches to allowable minimum speed.
Driving mode control
If the vehicle runs normally, fuel injection volume will be calculated by accelerator pedal travel and
engine rpm and the drive map will be used to match the drivers inputs with optimum engine power. -
-
-
Page 461 of 600

0000-00
This is done periodically under certain operating conditions. When the resetting is finished, the new
minimum pulse value replaces the value obtained during the previous resetting. The first MDP value is
provided by the C3I. Each resetting then allows the closed loop of the MDP to be updated according to
the deviation of the injector.
B. Detection of leaks in the cylinders
The accelerometer is also used to detect any injector which may have stuck open. The detection
principle is based on monitoring the ratio. If there is a leak in the cylinder, the accumulated fuel self-
ignites as soon as the temperature and pressure conditions are favorable (high engine speed, high load
and small leak).
This combustion is set off at about 20 degrees before TDC and before main injection.
The ratio therefore increases considerably in the detection window. It is this increase which allows the
leaks to be detected. The threshold beyond which a fault is signaled is a percentage of the maximum
possible value of the ratio.
Because of the severity of the recovery process (engine shut-down), the etection must be extremely
robust.
An increase in the ratio can be the consequence of various causes:
Pilot injection too much
Main combustion offset
Fuel leak in the cylinder -
-
-
If the ratio becomes too high, the strategy initially restricts the pilot injection flow and retards the main
injection. If the ratio remains high despite these interventions, this shows that a real leak is present, a
fault is signaled and the engine is shut down.
C. Detection of an accelerometer fault
This strategy permits the detection of a fault in the sensor or in the wiring loom connecting the sensor to
the ECU.
It is based on detection of the combustion. When the engine is idling, the detection window is set too low
for the combustion caused by the main injection. If the ratio increases, this shows that the knock sensor
is working properly, but otherwise a fault is signaled to indicate a sensor failure. The recovery modes
associated with this fault consist of inhibition of the pilot injection and discharge through the injectors.
Page 551 of 600
2) Fuel Injection During CDPF Regeneration
3) Warning Lamp Related To CDPF
The CDPF system enters the regeneration mode when
the driving distance becomes approx. 600 to 1,200 km
(may differ by the driving condition and driving style).
Then, the engine ECU performs the CDPF regeneration
operation. However, the driver is not informed with this
operation by any engine warning lamp or vehicle
signal, so he/she may not detect this operation. The
control logic at the post-injection during the
regeneration process is to increase the fuel injection
volume and control the intake air volume (by the throttle
body) in order to increase the temperature of the
exhaust gas. The driver may not feel any particular
difference from the vehicle.
No illuminating