ECD SYSTEM (w/ EGR Cooler Bypass Valve) Engine Difficult to Start or Stalling

DESCRIPTION


  1. Faults and Symptoms of Common Rail Diesel Components


    1. Engine Control

      Mass Air Flow Meter
      Component Mass air flow meter
      Main fault Decrease in performance (foreign matter is stuck)
      Symptoms Lack of power, black smoke
      Data List MAF

      Tech Tips

      The maximum fuel injection volume is controlled according to the output from the mass air flow meter.
      Intake System
      Component Intake system
      Symptom: Main fault

      • Lack of power (No black smoke): air filter blockage, air duct is crushed/leaking

      • Black smoke (No lack of power): Leakage between the turbo and intake manifold
      Data List

      • MAP (inside intake air pressure)

      • Target Booster Pressure

        When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds then a lack of power will be felt.
      Turbocharger System
      Component Turbocharger system
      Main fault

      • Air leak in the turbocharged air passage

      • Turbo motor driver not operating well

      • Turbocharger (turbine, bearing)
      Symptoms

      Lack of power (when vehicle starting, when heavy load)

      (Black smoke is not emitted when racing while vehicle stopped)
      Data List

      MAP (inside intake air pressure), Target Booster Pressure


      • When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds then a lack of power will be felt.

      • With the ignition switch ON or during idling, MAP = atmospheric pressure (standard atmospheric pressure = 101 kPa). When the engine speed is about 1500 rpm or more, the turbocharger starts to take effect and MAP becomes higher than atmospheric pressure.

      • Atmospheric pressure decreases 1 kPa each time altitude increases by 100 m, and is also affected by the current weather conditions.

      VN Turbo Command


      • 0%: Vanes fully open (drive rod contracts)

      • Over 90%: Vanes fully closed (drive rod expands and turbo operates effectively)
      Diagnostic Point

      • Using the Active Test "Test the Turbo Charger Step Motor", check the drive rod movement.

      • Check the drive rod movement when the ignition switch is turned from ON to off.
      Exhaust System
      Component Exhaust system
      Main fault Blockage
      Symptoms Lack of power (high engine speed, when heavy load)
      Data List

      MAP (inside intake air pressure)

      When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds then a lack of power will be felt.
      Glow System
      Component Glow system
      Main fault Open circuit, glow plug relay fault
      Symptoms Difficult to start, rough idle, knocking, white smoke (when cold)
      Data List Check the glow plug indicator light
      Diagnostic Point Try to measure the resistance of the glow plug
      Battery
      Component Battery
      Main fault Battery is depleted
      Symptoms Difficult to start (cannot crank, crank speed is low), horn is quiet.
      Data List

      Battery Voltage

      When cranking, battery voltage is below 5 V
      Engine - 1
      Component Engine
      Main fault Damaged, seized up
      Symptoms Cannot crank, crank speed is low, strange noise
      Engine - 2
      Component Engine
      Main fault Loss of compression
      Symptoms Rough idle (lack of power always)
      Data List

      Engine Speed of Cyl


      • When cranking during the "Check the Cylinder Compression" Active Test, if there is a high speed cylinder, approx. 100 rpm more than the other cylinders, that cylinder may lose compression.

      Injection Feedback Val


      • If Injection Feedback Val is more than 3 mm3/st, the cylinder may have a fault.
      Start System
      Component Start system
      Main fault Starter system malfunction
      Symptoms Difficult to start
      Data List

      Starter Signal


      • Ignition switch (STA) operation

        ON: Starter is operating

        OFF: Starter is not operating

    2. Diesel Injection

      Fuel Supply Pump
      Component Fuel supply pump
      Main fault -
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Fuel Press, Target Common Rail Pressure, Target Pump SCV Current


      • At a stable condition (e.g. Idling), Fuel Press is within +/-5000 kPa of "Target Common Rail Pressure".

      • If the fuel pressure is 20000 kPa below the target pressure then a lack of power will be felt.

      • If the fuel pressure is below 25000 kPa then idling will be rough.

      Tech Tips


      • The fuel pressure changes at engine starting, but is approx. 25000 kPa at engine start after the engine is warmed up.

      • When Target Pump SCV Current is 3000 mA or more, the suction control valve has a tendency to become stuck.
      Diagnostic Trouble Code Even if Fuel Press is less than Target Common Rail Pressure, a DTC will not be stored.
      Fuel Filter
      Component Fuel filter
      Main fault Blockage
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Fuel Press, Target Common Rail Pressure


      • At a stable condition (e.g. Idling), the fuel pressure is within +/-5000 kPa of "Target Common Rail Pressure ".

      • If the fuel pressure is 20000 kPa below the target pressure then a lack of power will be felt.

      • If the fuel pressure is below 25000 kPa then idling will be rough.

      Tech Tips

      The fuel pressure changes at engine starting, but is approx. 25000 kPa at engine start after the engine is warmed up.
      Diagnostic Trouble Code Even if Fuel Press is less than Target Common Rail Pressure, a DTC will not be stored.
      Fuel Injector
      Component Fuel injector
      Main fault Blockage
      Symptoms Rough idle, lack of power, black smoke, white smoke, knocking
      Data List

      Injection Feedback Val


      • When an Injection Feedback Val is more than 3 mm3/st, the cylinder is not normal. This can be read after idling for 1 minute with the engine warmed up (engine coolant temperature is higher than 70°C (158°F)).
      Pressure Discharge Valve
      Component Pressure discharge valve
      Main fault Does not completely close
      Symptoms Difficult to start, engine stall, rough idle, lack of power
      Injector Driver (EDU)
      Component Injector Driver (EDU)
      Main fault Circuit fault: The fuel injector does not open.
      Symptoms Difficult to start, rough idle, lack of power, black smoke, white smoke, knocking
      Data List Same as fuel injector
      Diagnostic Trouble Code When the EDU has a fault, some DTCs may be stored.
      Fuel Pressure Sensor
      Component Fuel pressure sensor
      Main fault Open circuit, decrease in performance (foreign matter is stuck)
      Symptoms Difficult to start, rough idle, engine stall, lack of power
      Data List

      Fuel Press, Target Common Rail Pressure


      • Slowly raise the engine speed from idling to 3000 rpm with the vehicle stopped, and check that Fuel Press follows Target Common Rail Pressure. If the fuel pressure sensor malfunctions, the actual fuel pressure may deviate from the target fuel pressure. (However, the value may not deviate even when a malfunction is present).
      Diagnostic Trouble Code When the fuel pressure sensor has a fault, some DTCs may be stored.
      Irregular Fuel
      Component Irregular fuel
      Main fault -
      Symptoms Difficult to start, rough idle (especially when cold)

    3. Diesel EGR

      EGR System
      Component EGR system
      Main fault

      • Does not move smoothly

      • Does not close completely
      Symptoms

      • Rough idle

      • EGR valve stuck closed: A loud turbocharger sound.

      • EGR valve stuck open: Difficult to start (does not stall), black smoke, lack of power (if there is an excess in the quantity of EGR and there is a heavy load, when the vehicle starts moving, a lack of power will be felt).
      Data List

      Actual EGR Valve Pos., Target EGR Pos.


      • Generally, Actual EGR Valve Pos. = Target EGR Pos. +/-5% (fully closed 0%, fully open 100%).

      • Using EGR valve Active Test, check whether Actual EGR Valve Pos. follows Target EGR Pos. (the engine coolant temperature and intake air temperature should be considered when a malfunction occurs).

      • EGR valve is fully closed when the ignition switch is turned to ON (engine stopped).

      • EGR valve opens to the halfway point at idling after the engine warmed up.

      EGR Close Lrn. Val., EGR Close Lrn. Status


      • When leaving the vehicle idling, when EGR Close Lrn. Status is OK, the normal range of EGR Close Lrn. Val. is 3.75 to 4.8 V.

      • In cases when EGR Close Lrn. Status. is NG or EGR Close Lrn. Val. is out of the normal range (3.75 to 4.8 V), it is possible that the EGR valve cannot completely close.

    4. Diesel Throttle

      Diesel Throttle System
      Component Diesel throttle system
      Main fault Stuck, does not move smoothly
      Symptoms

      • Stuck closed: Lack of power, difficult to start, rough idle, engine stall, black smoke. These may occur when stuck almost fully closed.

      • Stuck open: Turbocharger sound increases. When the engine is stopped, engine vibrations may occur.
      Data List

      • Actual Throttle Position

        0%: Fully open

        100%: Fully closed

      • When the ignition switch is ON (the engine is stopped), the diesel throttle is fully open. When idling, the diesel throttle is at the halfway point. When the ignition switch is turned from ON to off, the throttle is temporarily closed fully.

  2. Data List Related to Starting Trouble

    Note

    The Data List values in the table are the results of checking one vehicle under a specific condition (engine coolant temperature, intake air temperature, atmospheric pressure etc.). Therefore, use these values for reference only.


    1. Engine Control

      MAP
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      MAP

      • When MAP is low, there will be difficulty starting.

      • With ignition switch ON or during idling, MAP is nearly equal to Atmosphere Pressure (standard atmospheric pressure = 101 kPa).

      When MAP is low, the following conditions are possible:


      • Diesel throttle nearly fully closed.

      • Intake system blocked (turbocharger system also).

      • Exhaust system blocked.

      • When the ignition switch is ON or the vehicle is idling, MAP (intake manifold absolute pressure) and Atmosphere Pressure are approximately equal (standard atmospheric pressure = 101 kPa).

        Above approx. 1500 rpm, the turbo becomes effective, and the pressure becomes higher than atmospheric pressure.

      • Inspect while comparing with "Target Booster Pressure".

      • With the accelerator fully open, if the actual Manifold Absolute Pressure (MAP) is low compared to the target booster pressure by at least 20 kPa for 5 seconds or more, a feeling of insufficient power will occur.
      MAF
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      MAF -

      • MAF meter

      • MAF meter circuit

      • Intake system clogging, leaking

      • Exhaust system clogging

      • Turbocharger sub-assembly

      • Leaking or clogging of turbocharger passages

      • EGR valve does not close

      • Based on the MAF, the ECM controls the fuel injection volume, injection timing, EGR, etc.

      • If the value is always approximately 0 g/sec.:


        • Mass air flow meter power source circuit is open.

        • VG circuit is open or shorted.

        • EVG circuit is open.
      Intake Air
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Intake Air - Intake air temperature sensor.

      • After a long soak, the engine coolant temperature, intake air temperature and ambient air temperature are approximately equal.

      • If the value is -40°C (-40°F) or 140°C (284°F), the sensor circuit is open or shorted.
      Coolant Temp
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Coolant Temp

      • Engine coolant temperature is approximately equal to intake air temperature after leaving overnight. After warm-up: Engine coolant temperature is 70°C (158°F) or more.

      • In cases when the engine coolant temperature output is obviously higher than the actual engine coolant temperature, when it is cold, there will be difficulty starting due to problems with glow plugs or insufficient fuel injection.

      • In cases when the engine coolant temperature sensor output is obviously lower than the actual engine coolant temperature, when it is warm, there will be difficulty starting (black smoke will also occur) due to an excess of injected fuel.

      		 Engine coolant temperature sensor

      • If the value is -40°C (-40°F) or 140°C (284°F), the sensor circuit is open or shorted.

      • After a long soak, the coolant temperature, intake air temperature and ambient air temperature are approximately equal.
      Battery Voltage
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Battery Voltage When cranking, in cases when Battery Voltage becomes less than 5 V, the battery is depleted. Battery If 11 V or less, characteristics of some electrical components change.
      Starter Signal
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Starter Signal

      Operation of ignition switch (STA)

      ON: Starter is operating

      OFF: Starter is not operating

      		 Start system

      • Ignition switch (STA) output:


        • ON: Starter is operating

        • OFF: Starter is not operating
      Engine Speed of Cyl #1 (to #4)
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Engine Speed of Cyl #1 (to #4)

      When cranking, the engine speed of each cylinder is the same under normal conditions. When a cylinder is approximately 100 rpm higher than the other cylinders, it is conceivable that the compression of that cylinder is being lost.

      Tech Tips

      This data is output only when the Active Test "Check the Cylinder Compression" is performed.

      		 -

      • Output only when the Active Test "Check the Cylinder Compression" is performed.

      • With this Active Test, the fuel injection is stopped.

      • Indicates the speed of each cylinder when cranking.

        Example - Normal: "Engine speed" of all cylinders is approximately equal.

        No. 1 cylinder compression low: "Engine speed of Cyl#1" = approximately 300 rpm, "Engine speed of Cyl #2 to #4 cylinder" = approximately 200 rpm.

    2. Diesel Injection

      Target Common Rail Pressure
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target Common Rail Pressure - -

      • Inspect the (actual) fuel pressure, comparing it against the common rail target value.

      • Considered normal when the actual fuel pressure is within +/-5000 kPa of the target fuel pressure under stable conditions.
      Fuel Press
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Fuel Press

      • In a stable operating condition (e.g. idling), Fuel Press is Target Common Rail Pressure +/-5000 kPa.

      • During cranking, if Fuel Press is below 25000 kPa, there may be difficulty starting (take care as there is a response lag when the pressure rises).

      • When Fuel Press is below 25000 kPa, rough idling will occur.

      • If there is a fault with the fuel supply pump (lack of discharge quantity) or pressure discharge valve (will not fully close), the fuel pressure will drop. Also, a blocked fuel filter, leakage from fuel pipes, and lack of fuel will also make the fuel pressure drop.

      • If air mixes with the fuel, the fuel pressure will shift away from the target fuel pressure.

      • When there is a fault with the fuel supply pump, there is a possibility of lack of power, engine stall, rough idle and difficulty starting.

      • Fuel press is the actual common rail fuel pressure.

      • Inspect by comparing Fuel Press with Target Common Rail Pressure.

      • The ECM uses Fuel Press for feedback control of Target Fuel Pressure via the supply pump.

        The injection amount is determined based on the injection timing and fuel pressure.

        Also, the spray pattern is selected based on the fuel pressure.
      Target Pump SCV Current
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target Pump SCV Current Idling after warming up: roughly 950 to 1150 mA. When this value is large, the pump is trying to increase the fuel discharge rate.

      • With this data, component fault not specified, use this data as a reference.

      • If the current is 3000 mA or more, there is a possibility the suction control valve is stuck.

      • ECU-calculated value for the suction control valve actuation target current.


      • Value is large when a high fuel pressure is desired.

      • When this deviates from the standard value, it indicates that for some reason, even though the pump is running hard, the actual fuel pressure is inconsistent with the target fuel pressure.
      Injection Feedback Val #1 (to #4)
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Injection Feedback Val #1 (to #4)

      • When idling after the engine is warmed up, the fuel quantity of each fuel injector is corrected to make each cylinder engine speed equal.

      • Cylinders more than 3 mm3/st may have a fault.

      Tech Tips

      Read the value after one minute of idling after warm up (engine coolant temperature above 70°C (158°F)). This value is only calculated when idling.

      • Fault with a fuel injector or lack of compression of a cylinder with a large Injection Feedback Val.

      • Do a compression Active Test. If there is a cylinder that is around 100 rpm more than the other cylinders, there is a possibility that the compression of that cylinder is being lost.

      • If all the cylinder speeds are even according to the compression Active Test result, the fuel injector of the cylinder may have a fault.

      • With fuel injector faults, other than difficulty starting, there is a possibility of rough idling, lack of power, black smoke, white smoke and knocking.

      • When idling after warm up, the injection amount for each cylinder is corrected to optimize the difference of each cylinder engine speed.

        Example: For cylinders that are slowing the engine speed compared to other cylinders, the injection volume is increased.

      • "Injection Feedback Val" more than 3.0 mm3/st: Injector breakdown or insufficient compression is causing poor combustion.
      Injection Volume
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Injection Volume - -

      After warming up the engine, when Injection Volume during idling is 10 mm3/st or more, there is tendency for the injector to clog.

    3. Diesel Throttle

      Actual Throttle Position
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Actual Throttle Position

      • When the ignition switch is turned to ON (engine stopped), the diesel throttle is fully open. When the ignition switch is turned from ON to off, the diesel throttle is fully closed temporarily.

      • With the diesel throttle stuck almost fully closed, there is a possibility of rough idling, engine stall, black smoke, difficulty starting and lack of power.

      		 Diesel throttle body

      Actual Throttle Position is the closing percentage of the throttle valve.


      • Fully closed: 100%

      • Fully open: 0%

        Tech Tips

        There is no connection with the accelerator. However, under full load, the throttle is usually fully open (0%).

    4. Diesel EGR

      Target EGR Position
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target EGR Position - -

      • Fully open: 100%

      • Fully closed: 0%

      • Used for comparison to "Actual EGR Valve Pos".
      Actual EGR Valve Pos.
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Actual EGR Valve Pos.

      • Generally Actual EGR Valve Pos. = Target EGR Pos. (Fully closed = 0%, Fully open = 100%)

      • The EGR valve Active Test can be used to check whether the Actual EGR Valve Pos. = Target EGR Pos.

      		 EGR valve assembly

      • Inspect while comparing to "Target EGR Valve Pos.".

      • Sometimes the malfunction only occurs around a certain temperature, so refer to the engine coolant temperature and outside temperature at the time the malfunction occurred.
      EGR Close Lrn. Status
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      EGR Close Lrn. Status

      • "OK" means the fully closed position learning has completed normally.

      • When NG, the learned fully closed position may be outside of the normal range.

      		 - After disconnecting and reconnecting the battery cable, if the ignition switch has not been turned off once, learning may not be completed.
      EGR Close Lrn. Val.
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      EGR Close Lrn. Val. When leaving the vehicle idling, with the EGR Close Lrn. Status OK, the normal range of EGR Close Lrn. Val. is within 3.75 to 4.8 V. In cases when EGR Close Lrn. Status is NG or EGR Close Lrn. Val. is at the maximum or minimum (3.75 to 4.8 V) of the normal range, it is possible that the EGR valve is not completely closed or a foreign object is lodged in the EGR valve seat area. -

      • This value is the EGR position sensor output voltage.

      • As the maximum and minimum settings are 3.75 V and 4.8 V, if the value becomes stuck at either of these, there is a malfunction in the lift sensor or the valve position is shifted (due to foreign matter, etc.).

INSPECTION PROCEDURE


  1. Explanation of Symptom

    Starting Trouble

    For good starting it is essential to have:


    • Sufficient cranking speed.

    • Properly operating engine preheating system.

    • Good quality fuel.

    The fuel is ignited by the heat which is generated with compression pressure.

    With problems such as a depleted battery, the crankshaft speed can become low, or if the engine compression is leaking, the compression pressure will not rise and there will be difficulty starting.

    When the engine is cold, even if there is compression heat, it will escape from the combustion chamber. For this reason, when the engine is started when it is cold, the glow plugs heat the compressed air.

    Also, after starting the engine, by charging the glow plugs for a fixed time set according to the engine coolant temperature, diesel knocking and white smoke are prevented. The quantity of fuel injected is determined by the fuel pressure and also the amount of time the fuel injector is open.

  2. Trouble Area Chart According to Problem Cause

    A01KEF2E01
    A01KF3NE01

    Note


    • After replacing the ECM, the new ECM needs registration Click here and initialization Click here.

    • After replacing the fuel supply pump, the ECM needs initialization Click here.

    • After replacing a fuel injector, the ECM needs registration Click here.

    Tech Tips


    • Specified values in the following troubleshooting flowchart are for reference only. Variations in the Data List values may occur depending on the measuring conditions or the vehicle age. Do not assume the vehicle is normal when the Data List outputs standard values. There may be concealed factors of the malfunction.

PROCEDURE


  1. CHECK ENGINE CRANKING CONDITION


    1. Check the engine cranking condition.

      Result
      Result Proceed to
      Does not crank at all. A

      Low cranking speed.

      Tech Tips

      When cranking speed is low, especially when the temperature is low, check if the engine oil grade matches the recommendation.

      		 B
      Cranking is OK. C

    B

    CHECK BATTERY CONDITION Click here

    C

    CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL) Click here

    A

  2. CHECK BATTERY CONDITION


    1. Check the battery condition Click here.


    NG

    REPLACE BATTERY

    OK

  3. CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Check if the normal starting screen appears (check whether communication with the ECM is possible).

      Tech Tips

      Use a tester that is able to communicate with other vehicles.

      OK
      Communication is possible (vehicle can be recognized).

    NG

    CHECK VC OUTPUT CIRCUIT Click here

    OK

  4. READ VALUE USING INTELLIGENT TESTER (CLUTCH SWITCH)

    Tech Tips

    This inspection is not necessary for A/T vehicles.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Clutch Switch.

    4. Read the value displayed on the tester.

      Standard Value
      Tester Display Condition Specified Condition
      Clutch Switch Clutch pedal depressed ON
      Result
      Result Proceed to
      OK A
      NG B

    B

    REPLACE CLUTCH SWITCH ASSEMBLY Click here

    A

  5. READ ALL OUTPUT DTCS


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Utility / All Codes.

      Result
      Result Proceed to
      No DTC is output A
      DTCs related to engine are output B

    B

    GO TO RELATED DTC Click here

    A

    END

  6. CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL)


    1. Check if the fuel level is low.

      Result
      Result Proceed to
      The indicator (fuel warning light) is not illuminated A
      The indicator (fuel warning light) is illuminated B

    B

    ADD FUEL Click here

    A

  7. CHECK INITIALIZATION (FUEL SUPPLY PUMP)


    1. When the engine does not start or another problem such as rough idling is present, perform initialization and check to see if the problem symptoms disappear. If the problem symptoms do not disappear, perform the next procedure.

      Tech Tips

      When replacing the ECM, the supply pump initialization must be performed Click here.


    NEXT

  8. READ OUTPUT DTC (RELATED TO ENGINE)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / DTC.

    4. Read the DTCs.

      Result
      Result Proceed to
      No DTC is output A
      DTCs related to engine are output B

    B

    REPAIR OR REPLACE ENGINE CONTROL SYSTEM ACCORDING TO DTC OUTPUT Click here

    A

  9. TAKE SNAPSHOT DURING STARTING AND IDLING


    1. A01KG3HE39
      Text in Illustration
      *1 Snapshot Button

      Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data.

    4. Take a snapshot of the following Data List items with the intelligent tester during "ignition switch ON (5 seconds) → Starting → Idling (10 seconds)".

      Tech Tips


      • A snapshot can be used to compare vehicle data from the time of the malfunction to normal data and is very useful for troubleshooting. The data in the illustration below is that of a normal vehicle, but as the data varies between individual vehicles, this data should only be used for reference.

      • When there is trouble starting with a cold engine, take the snapshot when the engine is cold. Then warm up the engine (engine coolant temperature 70°C (158°F) or more) and after idling the vehicle for 1 minute (A/C off, electrical load off), take a snapshot of the data for 15 seconds while idling.

      • Graphs like the ones shown below can be displayed by transferring the stored snapshot from the tester to a PC. Intelligent Viewer must be installed on the PC.


    NEXT

  10. CHECK SNAPSHOT (TARGET PUMP SCV CURRENT)


    1. Check Target Pump SCV Current in the snapshot taken when the engine was starting.

      Result
      Result Proceed to
      Target Pump SCV Current is 3000 mA or more A
      Target Pump SCV Current is less than 3000 mA B

    A

    CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM) Click here

    B

  11. CHECK SNAPSHOT (FUEL PRESS)


    1. Check Fuel Press in the snapshot taken when the engine was starting.

      Result
      Result Proceed to

      2 seconds after Starter Signal turns from OFF to ON, Fuel Press is less than 20000 kPa

      Tech Tips

      As long as the fuel pressure remains below 5000 kPa, the ECM stops sending the injection open signal (IJT) to the EDU, and then the actual injection duration remains 0 microseconds.

      		 A
      2 seconds after Starter Signal turns from OFF to ON, Fuel Press is 50000 kPa or more B
      Except above C

      Tech Tips


      • Fuel pressure is about 20000 to 35000 kPa when the engine is cranking and the engine coolant temperature is 0°C (32°F) or more.

      • Fuel pressure increases rapidly during cranking.


    B

    CHECK SNAPSHOT Click here

    C

    INSPECT INJECTOR COMPENSATION CODE Click here

    A

  12. READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)


    1. A01KETN

      Using the hand pump mounted on the fuel filter cap, bleed the air from the fuel system. Continue pumping until the pump resistance increases.*1

      Note


      • Hand pump pumping speed: Maximum of 2 strokes/second.

      • Be sure to push the hand pump with a full stroke during pumping.

      • When the fuel pressure at the supply pump inlet port reaches a saturated pressure, the hand pump resistance increases.

      • If pumping is interrupted during the air bleeding process, fuel in the fuel line may return to the fuel tank. Continue pumping until the hand pump resistance increases.

      • If the hand pump resistance does not increase despite consecutively pumping 200 times or more, there may be a fuel leak between the fuel tank and fuel filter, the hand pump may be malfunctioning, or the vehicle may have run out of fuel.

      • If air bleeding using the hand pump is incomplete, the common rail pressure does not rise to the pressure range necessary for normal use, and the engine cannot be started.

    2. Start the engine.

      Note


      • Just after starting the engine, visually check for fuel leaks from the supply pump, fuel injector, common rail, and the fuel pipes in high-pressure areas.

      • Even if air bleeding using the hand pump has been completed, the starter may need to be cranked for 10 seconds or more to start the engine.

      • Do not crank the engine continuously for more than 20 seconds. The battery may be discharged.

      • Use a fully-charged battery.


      1. When the engine can be started, proceed to step *2.

      2. If the engine cannot be started, bleed the air again using the hand pump until the hand pump resistance increases (refer to step *1). Then start the engine.

    3. Turn the ignition switch off.*2

    4. Connect the intelligent tester to the DLC3.

    5. Turn the ignition switch to ON and turn the tester on.

    6. Clear DTCs Click here.

    7. Start the engine.*3

    8. Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak.*4

    9. Perform the following test 5 times with on/off intervals of 10 seconds: Active Test / Test the Fuel Leak.*5

    10. Allow the engine to idle for 3 minutes or more after performing the Active Test for the fifth time.*6

      A01KH8CE01

    11. Enter the following menus: Powertrain / Engine and ECT / DTC.

    12. Read Current DTCs.


      1. When no DTCs are output, the air bleeding is completed. Proceed to step *8.

      2. If any DTCs are output, proceed to step *7.

    13. Clear DTCs Click here.*7

    14. Repeat steps *3 to*6.

    15. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.*8

    16. Start the engine.

    17. Read the Fuel Press values while cranking and idling the engine.

      Result
      Result Proceed to
      The engine cannot be started or the engine can be started but Fuel Press is less than 20000 kPa 2 seconds after the starter signal changes from OFF to ON. B
      Except above A

    B

    INSPECT COMMON RAIL ASSEMBLY Click here

    A

    END

  13. CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM)


    1. Disconnect the S11 suction control valve connector.

    2. Disconnect the E11 ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      S11-1 - E11-23 (PCV+) Always Below 1 Ω
      S11-2 - E11-12 (PCV-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      S11-1 or E11-23 (PCV+) - Body ground Always 10 kΩ or higher
      S11-2 or E11-12 (PCV-) - Body ground Always 10 kΩ or higher

    4. Reconnect the suction control valve connector.

    5. Reconnect the ECM connector.


    OK

    CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  14. INSPECT COMMON RAIL ASSEMBLY


    1. Inspect the common rail assembly Click here.


    NG

    REPLACE COMMON RAIL Click here

    OK

  15. CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP


    1. Disconnect the inlet hose from the fuel supply pump.

    2. Operate the priming pump and check that fuel is being supplied to the fuel supply pump.

      OK
      Fuel is properly supplied to the fuel supply pump when the priming pump is operated.

      Tech Tips


      • When there is a lack of fuel, fuel pressure drops.

      • Inspect for fuel filter clogging (check that the fuel filter is not clogged).


    NG

    CHECK AND REPLACE CLOGGED FUEL PIPE (INCLUDING FUEL FREEZING) (FUEL TANK - FUEL SUPPLY PUMP) Click here

    OK

  16. REPLACE SUCTION CONTROL VALVE


    1. Replace the suction control valve Click here.


    NEXT

  17. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  18. PERFORM FUEL SUPPLY PUMP INITIALIZATION


    1. Perform fuel supply pump initialization Click here.


    NEXT

  19. READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    4. Start the engine.

    5. Read the Fuel Press values while cranking and idling the engine.

      Result
      Result Proceed to
      The engine cannot be started or the engine can be started but Fuel Press is less than 20000 kPa 2 seconds after the starter signal changes from OFF to ON. B
      Except above A

    B

    INSPECT FUEL INJECTOR (INSPECTION FOR VALVE CLOSING PROBLEM) Click here

    A

    END

  20. INSPECT FUEL INJECTOR (INSPECTION FOR VALVE CLOSING PROBLEM)


    1. Remove the glow plug assembly for all the cylinders Click here.

    2. Visually check if there is fuel on the glow plugs.

      Tech Tips


      • If there is fuel on a glow plug, fuel may be leaking from a fuel injector.

      • After replacing a fuel injector, make sure that the common rail pressure (fuel pressure) is within +/-5000 kPa of the target fuel pressure while cranking the engine.

      • If there is fuel on a glow plug, fuel may have mixed with the engine oil. Check the engine oil amount and whether the engine oil smells of diesel fuel. If the oil level is above the full line or the engine oil smells of diesel fuel, replace the engine oil.

      Result
      Result Proceed to
      No fuel on glow plugs A
      Fuel on glow plugs B

    3. Install the glow plug assembly Click here.


    B

    REPLACE FUEL INJECTOR OF MALFUNCTIONING CYLINDER Click here

    A

  21. REPLACE COMMON RAIL


    1. Replace the common rail Click here.


    NEXT

  22. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  23. READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    4. Start the engine.

    5. Read the Fuel Press values while cranking and idling the engine.

      Result
      Result Proceed to
      The engine cannot be started or the engine can be started but Fuel Press is less than 20000 kPa 2 seconds after the starter signal changes from OFF to ON. B
      Except above A

    B

    CHECK DATA LIST Click here

    A

    END

  24. INSPECT INJECTOR COMPENSATION CODE


    1. Read the injector compensation code Click here.

      OK
      Compensation codes stored in the ECM match compensation codes of the installed fuel injectors.

    NG

    REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING Click here

    OK

  25. CHECK DATA LIST


    1. A01KG3HE39
      Text in Illustration
      *1 Snapshot Button

      Check Injection Feedback Val # and Injection Volume in the snapshot taken when the engine was idling.

      Result
      Result Proceed to

      Injection Feedback Val #1 to #4 are 3 mm3/st or less

      Tech Tips

      There may be a malfunction in the corresponding cylinder.

      		 A

      Injection Feedback Val #1 to #4 are 3 mm3/st or less

      Injection Volume is more than 10 mm3/st

      		 B*

      Injection Feedback Val #1 to #4 are 3 mm3/st or less

      Injection Volume is 10 mm3/st or less

      		 C

      Tech Tips


      • *: When case "B" occurs, usually symptoms may be noticeable, such as difficult starting, rough idling, knocking or black smoke at high common rail pressure.

      • The shift lever should be in neutral and the A/C switch and all accessory switches should be off.


    B

    REPLACE FUEL INJECTORS OF ALL CYLINDERS Click here

    C

    CHECK TEMPERATURE WHEN STARTING TROUBLE OCCURS Click here

    A

  26. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE CYLINDER #1 TO #4 FUEL CUT)

    Tech Tips

    Use this Active Test to determine the malfunctioning cylinder.


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Cylinder #1 to #4 Fuel Cut.

      Tech Tips


      • If the engine idle speed does not change when a fuel injector is disabled, the cylinder being tested is malfunctioning.

      • If the cylinder being tested is normal, there will be a significant change in idle speed when the fuel injection is stopped for that cylinder.


    NEXT

  27. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CHECK THE CYLINDER COMPRESSION)

    Tech Tips

    Use this Active Test to help determine whether a cylinder has compression loss or not.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Check the Cylinder Compression / Data List / Compression / Engine Speed of Cyl #1 to #4.

    4. Check the engine speed during the Active Test.

      OK
      The values of Engine Speed Cyl #1 to #4 are within +/-10 rpm of each other.

      Tech Tips

      When cranking, if the speed of a cylinder is approximately 100 rpm more than the other cylinders, there is probably a loss of compression in that cylinder.


    OK

    REPLACE FUEL INJECTOR OF MALFUNCTIONING CYLINDER Click here

    NG

    CHECK CYLINDER COMPRESSION PRESSURE OF MALFUNCTIONING CYLINDER Click here

  28. CHECK CYLINDER COMPRESSION PRESSURE OF MALFUNCTIONING CYLINDER

    Tech Tips

    Measure the compression of the cylinder that had a high speed during the Active Test "Check the Cylinder Compression".


    1. Check the cylinder compression pressure Click here.


    NG

    CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

    OK

  29. REPLACE FUEL INJECTOR OF MALFUNCTIONING CYLINDER

    Tech Tips

    The injector is determined to be faulty as the corresponding cylinder is malfunctioning, but has no compression loss.


    1. Replace the fuel injector Click here.


    NEXT

    BLEED AIR FROM FUEL SYSTEM Click here

  30. CHECK TEMPERATURE WHEN STARTING TROUBLE OCCURS


    1. Check the temperature when starting trouble occurs.

      Result
      Result Proceed to
      Difficult to start only for cold engine. A
      Difficult to start both for cold and warmed up engine. B

    B

    CHECK FUEL QUALITY Click here

    A

  31. INSPECT ENGINE COOLANT TEMPERATURE SENSOR


    1. Inspect the engine coolant temperature sensor Click here.


    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here

    OK

  32. INSPECT GLOW PLUG ASSEMBLY (RESISTANCE)

    A01KENJ

    1. Disconnect the glow plug wire.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Glow plug terminal - Body ground 20°C (68°F) Approximately 0.7 Ω

      Tech Tips

      If any of the glow plugs has an open circuit, the engine power will be insufficient only when the engine is cold.

      Note


      • Exercise extreme care not to damage the glow plug pipes. Damaging them could cause an open circuit or shorten the life of the glow plugs.

      • Keep the glow plugs free of oil and fuel while cleaning.

      • Wipe any oil off of the terminal and Bakelite washer with a clean, dry cloth during inspection.

      • Do not apply higher than 11 V to the glow plugs as it may cause an open circuit.


    NG

    REPLACE GLOW PLUG ASSEMBLY Click here

    OK

  33. CHECK FUEL QUALITY


    1. Check that fuel with a low cetane number is used.


    NEXT

  34. CHECK ENGINE STARTING CONDITION


    1. Check whether the engine can be started.

      Tech Tips

      If there are deposits in the injectors and they are left for a long time, the injectors for all the cylinders may become stuck.

      Result
      Result Proceed to
      The engine can be started. A
      There is no initial combustion even when the engine can be cranked. B

    B

    REPLACE FUEL INJECTORS OF ALL CYLINDERS Click here

    A

  35. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check whether the difficulty starting has been successfully repaired by starting the engine.


    NEXT

    END

  36. CHECK SNAPSHOT

    Tech Tips

    When all Data List values are OK and Fuel Press is higher than Target Common Rail Pressure, perform the following inspection.


    NEXT

  37. INSPECT INJECTOR DRIVER (EDU POWER SOURCE)


    1. A01KIGME02
      Text in Illustration
      *1 EDU Connector
      *a Wire Harness Side
      *b Front view

      Disconnect the E14 injector driver (EDU) connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E14-2(+B) - E14-3(GND) Ignition switch ON 11 to 14 V

    3. Reconnect the injector driver (EDU) connector.


    NG

    GO TO INJECTOR CIRCUIT Click here

    OK

  38. INSPECT FUEL INJECTOR

    Tech Tips

    If there is no initial combustion during cranking, there may be air in the injectors.


    NEXT

    END

  39. REPLACE FUEL INJECTORS OF ALL CYLINDERS


    1. Replace the fuel injectors Click here.


    NEXT

  40. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  41. REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING


    1. Register the injector compensation codes Click here.

    2. Perform the fuel injector pilot quantity learning Click here.


    NEXT

  42. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    4. Start the engine.

    5. Read the Fuel Press values while cranking and idling the engine.

      OK
      The engine can be started and Fuel Press is 20000 kPa or higher 2 seconds after the starter signal changes from OFF to ON.

    NEXT

    END

  43. CHECK AND REPLACE CLOGGED FUEL PIPE (INCLUDING FUEL FREEZING) (FUEL TANK - FUEL SUPPLY PUMP)


    1. Check and replace the clogged fuel pipe.


    NEXT

    BLEED AIR FROM FUEL SYSTEM Click here

  44. ADD FUEL


    1. Add fuel.


    NEXT

  45. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  46. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    4. Start the engine.

    5. Read the Fuel Press values while cranking and idling the engine.

      OK
      The engine can be started and Fuel Press is 20000 kPa or higher 2 seconds after the starter signal changes from OFF to ON.

    NEXT

    END

  47. CHECK VC OUTPUT CIRCUIT


    1. Check the VC output circuit Click here.


    NEXT

  48. CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Check if the normal starting screen appears (check whether communication with the ECM is possible).

      Tech Tips

      Use a tester that is able to communicate with other vehicles.

      OK
      Communication is possible (vehicle can be recognized).

    NG

    CHECK ECM POWER SOURCE CIRCUIT Click here

    OK

    END

  49. CHECK ECM POWER SOURCE CIRCUIT


    1. Check the ECM power source circuit Click here.


    NEXT

  50. CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Check if the normal starting screen appears (check whether communication with the ECM is possible).

      Tech Tips

      Use a tester that is able to communicate with other vehicles.

      OK
      Communication is possible (vehicle can be recognized).

    NG

    REPLACE ECM Click here

    OK

    END