03-18
Pressure leak test in fuel system with scan tool ▶
When the dynamic test for injector backleak is performed, this test should be done together with it.
However, you can check the pressure leak from the fuel system only with this test.
<007b00960047008b00960047009b008f0090009a0047009b008c009a009b00530047009b008f008c0047008a00960096009300880095009b0047009b008c00940097008c00990088009b009c0099008c0047009a008f0096009c0093008b00470089008c00
470096009d008c00990047005d0057020b006a00550047006a>heck the conditions of sensors
and components in fuel system with scan tool.
Perform the diagnostic test as follows: 1.
2.
3.
Select the "Vehicle Model" and go to "Diagnosis Mode".
Select "Pressure Leak Test in Fuel System" in "Diagnosis Menu".
If the conditions are OK, press "Start". -
-
-
The pressure leak test procedure is performed in 4 cycles. The engine speed goes up to
3,500 rpm and down again four times for 18 seconds. If the system is OK, the "System OK"
message will be displayed.
12-118530-00
5) ECO Cruise Control
The ECO cruise control system has nearly same functions with the auto cruise control system. It is an
automatic speed control system that maintains a desired driving speed without using the accelerator
pedal.
ECO cruise driving mode
The engine ECU controls the sharp acceleration and deceleration to improve the fuel economy.
The ECO cruise system is ready when pushing down the cruise control lever. At this moment, the
ECO indicator on the instrument cluster comes on.
The ECO cruise system operates when pulling up the cruise control lever.
To cancel the ECO cruise driving, push doen the cruise control lever. At this moment, the ECO
indicator on the instrument cluster goes off and the auto cruise starts to operate. -
-
-
-
Control leverECO indicator
ON Blinking
Push down the lever O
Push down it again O
14-51114-00
(3) Warning Lamp Related to CDPF
CDPF regeneration process (warning lamp NOT illuminated) ▶
Overload of CDPF (warning lamp blinking) ▶
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.
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.
15-90000-00
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.
<00760097008c00990088009b00900095008e0047009b008c00940097008c00990088009b009c0099008c0047009900880095008e008c00470096008d0047006c006a007c00470090009a0047009500960099009400880093009300a000470054005b005700
47009b009600470052005f005c00b6006a004700880095008b> protected from factors like oil,
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. -
-
-
15-18
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 accelerometer
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.
12-118530-00
5) ECO Cruise Control
The ECO cruise control system has nearly same functions with the auto cruise control system. It is an
automatic speed control system that maintains a desired driving speed without using the accelerator
pedal.
ECO cruise driving mode
The engine ECU controls the sharp acceleration and deceleration to improve the fuel economy.
The ECO cruise system is ready when pushing down the cruise control lever. At this moment, the
ECO indicator on the instrument cluster comes on.
The ECO cruise system operates when pulling up the cruise control lever.
To cancel the ECO cruise driving, push doen the cruise control lever. At this moment, the ECO
indicator on the instrument cluster goes off and the auto cruise starts to operate. -
-
-
-
Control leverECO indicator
ON Blinking
Push down the lever O
Push down it again O
15-91490-00
3. ECU CONTROL
1) Functions
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 activates the 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 autocruise and immobilizer and adopted
CAN communication to exchange data among electrical systems (automatic T/M and brake system) in
the vehicle fluently. And the diagnostic tool can be used to diagnose vehicle status and defectives.
<00760097008c00990088009b00900095008e0047009b008c00940097008c00990088009b009c0099008c0047009900880095008e008c00470096008d0047006c006a007c00470090009a0047009500960099009400880093009300a000470054005b005700
47009b009600470052005f005c00b6006a004700880095008b> protected from factors like oil,
water and electromagnetism and there should be no mechanical shocks.
2) Control Functions
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. -
-
-
15-150000-00
(4) Features
Determines the ignition timing according to input signal
The ECU always analyzes the following elements when determining the ignition timing. 1.
Crankshaft position sensor
Camshaft position sensor
Coolant temperature sensor
Intake air temperature/air mass -
-
-
-
Warm-up of catalytic converter
The ignition timing is retarded for about 20 seconds to operate the catalytic converter according to the
operating temperature under the following conditions: 2.
<007b008f008c0047008a00960096009300880095009b0047009b008c00940097008c00990088009b009c0099008c00470090009a00470058005c00b6006a004700a50047005b005700b6006a00470088009b0047009a009b00880099009b00900095008e00
55>
The idle speed is increased by the idle speed control to help warming up of the catalytic converter -
-
Idle speed control
<007b008f008c00470090008e00950090009b0090009600950047009b0090009400900095008e0047008a0088009500470089008c00470099008c009b00880099008b008c008b0047009c00970047009b00960047005a005d00b60047009600990047008800
8b009d00880095008a008c008b0047009c00970047009b0096> 20˚ to help idle speed control.
The ignition timing control can be performed faster than the control through the throttle valve.
Fuel cut-off in deceleration
The ignition timing is retarded temporarily to prevent abrupt increase of the torque when the
combustion is restarted.
Intake air temperature/coolant temperature
The ignition timing is retarded to prevent knocking if the intake air temperature or coolant temperature
is high. The ignition timing is retarded in the following cases. 3.
4.
5.
The intake air temperature is above 30°C.
The coolant temperature is above 105°C. -
-
The ignition timing retard for intake air temperature and for coolant temperature is added up for
correction.
ESP/ASR control mode
The ignition timing is retarded to reduce engine torque as fast as possible under the ESP/ASR
control mode.
Knocking control
If knocking occurs in the cylinder, the ignition angle of the corresponding cylinder is retarded. The
coolant temperature is 15˚C to 40˚C when starting. 6.
7.