DESCRIPTION
Faults and Symptoms of Common Rail Diesel Components
Engine Control
| Component | Mass air flow meter | |
| Main fault | Decrease in performance (foreign matter is stuck) | |
| Symptoms | Lack of power, black smoke | |
| Data List | MAF | |
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Tech Tips The maximum fuel injection volume is controlled according to the output from the mass air flow meter. |
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| Component | Intake system | |
| Symptom: Main fault |
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| Data List |
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| Component | Turbocharger system | |
| Main fault |
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| Symptoms | Lack of power (when vehicle starting, when vehicle under heavy load) (Black smoke is not emitted when racing while vehicle stopped) |
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| Data List | MAP (inside manifold absolute pressure), Target Booster Pressure
VN Turbo Command
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| Diagnostic Point |
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| Component | Exhaust system | |
| Main fault | Blockage | |
| Symptoms | Lack of power (high engine speed, when vehicle under heavy load) | |
| Data List | MAP (inside manifold absolute pressure) When the accelerator is fully depressed, if MAP is 15 kPa lower than Target Booster Pressure for more than 5 seconds then a lack of power will be felt. |
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| 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 | |
| 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 less than 5 V |
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| Component | Engine | |
| Main fault | Damaged, seized up | |
| Symptoms | Cannot crank, crank speed is low, strange noise | |
| Component | Engine | |
| Main fault | Loss of compression | |
| Symptoms | Rough idle (lack of power always) | |
| Data List | Engine Speed of Cyl
Injection Feedback Val
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| Component | Entry and start system | |
| Main fault | Starter system malfunction | |
| Symptoms | Difficult to start | |
| Data List | Starter Signal
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| Component | Engine immobiliser system | |
| Main fault | Engine immobiliser system (w/ Entry and Start System) / Problem Symptoms Table Click here Engine immobiliser system (w/o Entry and Start System) / Problem Symptoms Table Click here |
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| Symptoms | Engine does not start | |
| Data List | Immobiliser Communication
Engine Immobiliser System (w/ Entry and Start System) / Data List Click here Engine Immobiliser System (w/o Entry and Start System) / Data List Click here |
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Diesel Injection
| 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
Tech Tips
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| Diagnostic Trouble Code | Even if Fuel Press is less than Target Common Rail Pressure, a DTC may not be stored. | |
| 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
Tech Tips The fuel pressure changes at engine starting, but is approx. 25000 kPa at engine start after the engine is warmed up. |
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| Diagnostic Trouble Code | Even if Fuel Press is less than Target Common Rail Pressure, a DTC may not be stored. | |
| Component | Fuel injector | |
| Main fault | Injection hole blockage Nozzle needle or valve piston does not move smoothly |
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| Symptoms | Rough idle, lack of power, black smoke, white smoke, knocking | |
| Data List | Injection Feedback Val
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| Component | Pressure control valve | |
| Main fault | Does not completely close | |
| Symptoms | Difficult to start, engine stall, rough idle, lack of power | |
| 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
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| Diagnostic Trouble Code | When the fuel pressure sensor has a fault, some DTCs may be stored. | |
| Component | Irregular fuel | |
| Main fault | - | |
| Symptoms | Difficult to start, rough idle (especially when cold) | |
Diesel EGR
| Component | EGR system | |
| Main fault |
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| Symptoms |
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| Data List | Actual EGR Valve Pos., Target EGR Pos.
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Diesel Throttle
| Component | Diesel throttle system | |
| Main fault | Stuck, does not move smoothly | |
| Symptoms |
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| Data List |
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Data List Related to Starting Trouble
Tech Tips
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.
Engine Control
| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| MAP |
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When MAP is low, the following conditions are possible:
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| Results of real-vehicle check:
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| MAF | - |
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| Results of real-vehicle check:
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Tech Tips
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Intake Air | - | Intake air temperature sensor. |
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Coolant Temp |
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Engine coolant temperature sensor |
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| 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. |
| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Starter Signal | Operation of ignition switch (START) ON: Starter is operating OFF: Starter is not operating |
Starting system |
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| 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 Usually the tester displays the value of when the engine is started. |
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Immobiliser Communication | Engine Immobiliser System (w/ Entry and Start System) / Data List Click here Engine Immobiliser System (w/o Entry and Start System) / Data List Click here |
Engine Immobiliser System (w/ Entry and Start System) / Problem Symptoms Table Click here Engine Immobiliser System (w/o Entry and Start System) / Problem Symptoms Table Click here |
When there is a malfunction in the immobiliser system (w/ Entry and Start System), a DTC is stored Click here When there is a malfunction in the immobiliser system (w/o Entry and Start System), a DTC is stored Click here |
Diesel Injection
| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Target Common Rail Pressure | - | - |
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| Results of real-vehicle check:
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Fuel Press |
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| Results of real-vehicle check:
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Target Pump SCV Current | 1530 mA or less |
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| Results of real-vehicle check:
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Injection Feedback Val #1 (to #4) |
Tech Tips Read the value after one minute of idling after warm up (engine coolant temperature above 75°C (167°F)). This value is only calculated when idling. |
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Injection Volume | - | - | If injectors are clogged, fuel quality is poor, the fuel filter is clogged, or engine friction increases, then "Injection Volume" will increase. |
| Results of real-vehicle check:
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Diesel Throttle
| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Actual Throttle Position |
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Diesel throttle body | Closing percentage of the throttle valve.
If there is a malfunction of the throttle actuator, compare the target and actual throttle position values for the troubleshooting. |
| Results of real-vehicle check:
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Diesel EGR
| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Target EGR Position | - | - |
Tech Tips If the time of engine idling is long (approximately 20 minutes or more), EGR will be cut off. At this time, if the vehicle is driven in 5th gear at 70 km/h for 10 minutes, EGR resumes. |
| Results of real-vehicle check:
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| Data List | Judgment of Data List Values | Faulty Component | Diagnosis Note |
|---|---|---|---|
| Actual EGR Valve Pos. |
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EGR valve assembly |
Tech Tips If the time of engine idling is long (approximately 20 minutes or more), EGR will be cut off. At this time, if the vehicle is driven in 5th gear at 70 km/h for 10 minutes, EGR resumes. |
| Results of real-vehicle check:
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Actual Examples of Malfunction
Tech Tips
The purpose of the following examples is to help you understand the relationship between each Data List item when a certain malfunction occurs. Understanding this relationship helps you find the root cause easier.
The following are examples of actual malfunctions of a common rail diesel engine.
Use them for reference when diagnosing malfunctions.
These are not data of IQ 1ND-TV.
Fuel is not being supplied to supply pump (Low pressure fuel line clogged)
Fuel is not being injected (Injectors are leaking)
Fuel supply pump malfunction (suction control valve momentarily sticking)
Increased opening delay of injectors (Internal contamination)
WIRING DIAGRAM
Refer to DTC P1228 Click here.
INSPECTION PROCEDURE
Explanation of Symptom
| Starting Trouble | For good starting it is essential to have:
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. |
Trouble Area Chart According to Problem Cause
Note
When replacing the ECM and/or fuel injector, the ECM needs Registration and Initialization Click here.
Tech Tips
When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initializations/ registrations for the "Learning Values Write" function by following the instructions shown on the tester display.
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 to be normal when the Data List outputs standard values. There may be concealed factors of the malfunction.
PROCEDURE
CHECK ENGINE CRANKING CONDITION
Check the engine cranking condition.
| 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. |
A |
| Cranking is OK. | B |
| B |
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CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL) Click here |
| A |
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CHECK BATTERY CONDITION
Check the battery condition Click here.
| NG |
|
REPLACE BATTERY |
| OK |
|
CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
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 |
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CHECK VC OUTPUT CIRCUIT Click here |
| OK |
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READ VALUE USING INTELLIGENT TESTER (CLUTCH SWITCH)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Clutch Switch.
Read the value displayed on the tester.
| OK | ||||||
|---|---|---|---|---|---|---|
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| NG |
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REPLACE CLUTCH START SWITCH Click here |
| OK |
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READ ALL OUTPUT DTCS
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Utility / All Codes.
| Result | Proceed to |
|---|---|
| No DTC is output | A |
| DTCs related to engine are output | B |
| B |
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GO TO RELATED DTC |
| A |
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CHECK DOOR CONTROL TRANSMITTER FUNCTION (W/ ENTRY AND START SYSTEM)
Check if the "Door Control Transmitter" function of each key functions properly.
Tech Tips
Check if the engine starts properly with another key.
If the doors cannot be opened/closed by using the "Door Control Transmitter" function of the key, the battery inside the key may be depleted. In such a case, the engine cannot be started by pushing the engine switch.
When the door control transmitter battery is depleted, the engine can only be started by holding the door control transmitter against the engine switch.
If the inspection result is that the problem only occurs in certain locations or times of day, the possibility of wave interference is high. Also, added vehicle components may cause wave interference. If any optional components are installed, remove them and perform the operation check.
Near broadcasting stations, large screens, airports, transformer stations, gasoline stations, etc., the door control transmitter may not operate due to electric wave interference.
| NEXT |
|
CHECK STARTER SIGNAL CIRCUIT
Tech Tips
Check that "Starter Signal" in the Data List changes to ON when the engine is started.
Inspect the Starter Signal Circuit Click here.
| NEXT |
|
END
CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL)
Check if the fuel level is low.
| Result | Proceed to |
|---|---|
| The fuel gauge (segment) does not blink | A |
| The fuel gauge (segment) blinks | B |
| B |
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ADD FUEL Click here |
| A |
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READ OUTPUT DTC (RELATED TO ENGINE)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Read pending DTCs.
| Result | Proceed to |
|---|---|
| No DTC is output | A |
| DTCs related to engine are output | B |
| B |
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REPAIR OR REPLACE ENGINE CONTROL SYSTEM ACCORDING TO DTC OUTPUT Click here |
| A |
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TAKE SNAPSHOT DURING STARTING AND IDLING
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Tech Tips
The shift lever should be in neutral and the A/C switch and all accessory switches should be off.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data.
Take a snapshot of the following Data List items with the intelligent tester during "ignition switch ON (5 seconds) → Starting → Idling (60 seconds)".
Warm up the engine until the engine coolant temperature reaches 75°C (167°F) or more and after idling the vehicle for 1 minute.
Tech Tips
The shift lever should be in neutral and the A/C switch and all accessory switches should be off.
Take a snapshot of the following Data List items with the intelligent tester during "ignition switch ON (5 seconds) → Starting → Idling (60 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.
Detailed graphs can be displayed by transferring the stored snapshot data from the tester to a PC (personal computer) with Intelligent Viewer installed.
| Data List | |
|---|---|
| Starter Signal | |
| Engine Speed | |
| Fuel Press | |
| Target Common Rail Pressure | |
| Target Pump SCV Current | |
| Injection Volume | |
| Main Injection Period | |
| Battery Voltage | |
| Actual EGR Valve Pos. | |
| Target EGR Position | |
| Actual Throttle Position | |
| Target Throttle Position | |
| MAF | |
| Target Booster Pressure | |
| MAP |
| Data List | Value | Unit |
|---|---|---|
| Starter Signal | ON | - |
| Engine Speed | 295 | rpm |
| Fuel Press | 21920 | kPa |
| Target Common Rail Pressure | 21470 | kPa |
| Injection Volume | 19.58 | mm3/st |
| Main Injection Period | 639 | μs |
| Battery Voltage | 10.5 | V |
| Target EGR Position | 0.0 | % |
| Actual EGR Valve Pos. | 0.3 | % |
| Actual Throttle Position | -1 | % |
| MAF | 2.72 | gm/sec |
| MAP | 99 | kPa |
| Target Boost Pressure | 106.36 | kPa |
| Coolant Temp | 64 | °C |
| Data List | Value | Unit |
|---|---|---|
| Engine Speed | 773 | rpm |
| Target Booster Pressure | 100.97 | kPa |
| MAP | 99 | kPa |
| MAF | 5.05 | gm/sec |
| Target Common Rail Pressure | 25000 | kPa |
| Fuel Press | 25210 | kPa |
| Injection Volume | 4.58 | mm3/st |
| Actual EGR Valve Pos. | 55.6 | % |
| Actual Throttle Position | 0 | % |
| Target EGR Position | 56.0 | % |
| Coolant Temp | 88 | °C |
Tech Tips
Actual Examples of Malfunction (See "Diagnostic Help" menu)
Starting is not possible
Fuel is not supplied to supply pump.
Fuel Press: Approximately 1000 kPa or less during cranking.
Air in injectors.
Fuel Press: 60000 to 70000 kPa during cranking.
Cranking time is long
Suction control valve is stuck.
Target Pump SCV Current intermittently reaches 1530 mA or more. The suction control valve plunger intermittently becomes stuck. If there is difficulty starting when the engine is cold, cool the engine and inspect it.
Injector clogging or internal contamination:
Injection Feedback Val # of one or more of the cylinders is 2 mm3/st or more.
Injection Feedback Val # can be read when the engine is idling after being warmed up.
| NEXT |
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CHECK SNAPSHOT (TARGET PUMP SCV CURRENT)
Check Target Pump SCV Current in the snapshot taken when the engine had been idling more than 10 seconds after the engine was started.
| Result | Proceed to |
|---|---|
| Target Pump SCV Current is less than 1530 mA | A |
| Target Pump SCV Current is 1530 mA or more | B |
Tech Tips
If the engine could not be started, proceed to A.
| B |
|
CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM) Click here |
| A |
|
CHECK SNAPSHOT (FUEL PRESS)
Check Fuel Press in the snapshot taken when the engine was starting.
| Result | Proceed to |
|---|---|
| Fuel Press is less than 20000 kPa | A |
| Fuel Press is 20000 kPa or more | B |
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 INJECTOR COMPENSATION CODE Click here |
| A |
|
READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)
| *1 | Hand pump |
Using the hand pump mounted on the fuel filter cap, bleed the air from the fuel system. Continue pumping until the pump resistance increases (A).
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.
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.
When the engine can be started, proceed to step B.
If the engine cannot be started, bleed the air again using the hand pump until the hand pump resistance increases (refer to step A). Then start the engine.
Turn the ignition switch off (B).
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Clear DTCs Click here.
Start the engine (C).
Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak (D).
Maintain the engine speed of 3500 rpm, and then press the "Start" button (E).
Perform the following test 5 times with on/off intervals of 10 seconds: Active Test / Test the Fuel Leak (F).
Allow the engine to idle for 3 minutes or more after performing the Active Test for the fifth time (G).
Tech Tips
When the Active Test "Test the Fuel Leak" is used to change the pump control mode, the actual fuel pressure inside the common rail drops below the target fuel pressure when the Active Test is off, but this is normal and does not indicate a pump malfunction.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Read Current DTCs.
When no DTCs are output, the air bleeding is completed. Proceed to step I.
If any DTCs are output, proceed to step H.
Clear DTCs Click here (H).
Repeat steps C to G.
Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press (I).
Start the engine.
Read the Fuel Press value while cranking and idling the engine.
| Result | Proceed to |
|---|---|
| The engine can be started and Fuel Press is 20000 kPa or more. | A |
| The engine cannot be started or the engine can be started but the Fuel Press is less than 20000 kPa during cranking. | B |
| B |
|
CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP Click here |
| A |
|
END
CHECK INJECTOR COMPENSATION CODE
Read the injector compensation code Click here.
| OK |
|---|
| Compensation codes stored in the ECM match compensation codes of the installed fuel injectors. |
| NG |
|
PERFORM REGISTRATION AND INITIALIZATION Click here |
| OK |
|
CHECK DATA LIST (INJECTION VOLUME AND INJECTOR FEEDBACK VAL #1 TO #4)
Check Injection Feedback Val # and Injection Volume in the snapshot taken when the engine was idling.
| Result | Proceed to |
|---|---|
| Injection Feedback Val #1 to #4 is outside the range of +/-2 mm3/st Tech Tips There may be a malfunction in the corresponding cylinder. |
A*1 |
| Injection Feedback Val #1 to #4 is within the range of +/-2 mm3/st and Injection Volume is more than 8 mm3/st |
B*2 |
| Injection Feedback Val #1 to #4 is within the range of +/-2 mm3/st and Injection Volume is 8 mm3/st or less |
C |
Tech Tips
*1: If there is an open or short in a glow plug, case A occurs only with a cold engine.
*2: When case "B" occurs, usually symptoms may be noticeable, such as difficult starting, rough idling, knocking or black smoke at high common rail pressure.
If the value of Injection Volume is more than 8 mm3/st and the value of all of the Injector Feedback Val. #1 to #4 is within the threshold, replace the fuel injectors for all cylinders.
In this case, there is a possibility that too much recirculated exhaust gas enters into the engine. Therefore, you should compare the Target EGR Position with the Actual EGR Valve Pos. by entering the following menus using the intelligent tester:
Powertrain / Engine and ECT / Data List / Target EGR Position and Actual EGR Valve Pos.
If the difference between Target EGR Position and Actual EGR Valve Pos. exceeds +/-10%, the EGR system may have a malfunction.
| B |
|
REPLACE INJECTOR ASSEMBLY OF ALL CYLINDERS Click here |
| C |
|
CHECK TEMPERATURE WHEN STARTING TROUBLE OCCURS Click here |
| A |
|
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (FUEL CUT FOR IDENTIFYING MALFUNCTIONING CYLINDER)
Tech Tips
Use this Active Test to determine the malfunctioning cylinder.
Connect the intelligent tester to the DLC3.
Start the engine and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Cylinder #1 to #4 Fuel Cut.
Check the 4 cylinders in sequence to identify a faulty cylinder by performing the Active Test / Control the Cylinder #1 to #4 Fuel Cut inspection.
Tech Tips
DTCs may be output after this Active Test. Make sure to check for DTCs after this Active Test. If any DTCs are output, make sure to clear them Click here.
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 |
|
READ VALUE USING INTELLIGENT TESTER (ENGINE SPEED OF CYL #1 TO #4)
Tech Tips
The speed of each cylinder can be measured (compression test) by using the intelligent tester.
In the compression test, disconnect the injector connectors of all cylinders and crank the engine for approximately 10 seconds. At this time, the speed of each cylinder is measured. If the speed of one cylinder is higher than the other cylinders, the compression pressure of that cylinder is determined to be lower than the other cylinders.
Warm up the engine.
Turn the ignition switch off and disconnect the injector connector of all cylinders.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Engine Speed of Cyl #1, Engine Speed of Cyl #2, Engine Speed of Cyl #3, Engine Speed of Cyl #4 and Av Engine Speed of All Cyl.
Crank the engine for about 10 seconds.
Note
Do not crank the engine for more than 20 seconds.
Use a fully-charged battery.
Read the engine speed (Engine Speed of Cyl #1 to #4, Av Engine Speed of All Cyl) displayed on the tester when the ignition switch is ON.
Tech Tips
Do not turn the ignition switch off when finished cranking.
| Result | Proceed to |
|---|---|
| Except below | A |
| The values of Engine Speed Cyl #1 to #4 are within +/-10 rpm of each other. | B |
Tech Tips
When cranking, if the speed of a cylinder is approximately 100 rpm more than the other cylinders, there is probably a complete loss of compression in that cylinder.
Reconnect the injector connector of all cylinders.
Clear the DTCs.
| B |
|
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER Click here |
| A |
|
CHECK CYLINDER COMPRESSION PRESSURE OF MALFUNCTIONING CYLINDER
Check the cylinder compression pressure Click here.
| OK |
|---|
| The cylinder compression pressure is within the standard range. |
| NG |
|
CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION |
| OK |
|
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER
Tech Tips
The injector is determined to be faulty as the corresponding cylinder is malfunctioning but has no compression loss.
Replace the injector assembly Click here.
| NEXT |
|
PERFORM REGISTRATION AND INITIALIZATION Click here |
CHECK TEMPERATURE WHEN STARTING TROUBLE OCCURS
Check the temperature when starting trouble occurs.
| 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 |
|
INSPECT ENGINE COOLANT TEMPERATURE SENSOR
Inspect the engine coolant temperature sensor Click here.
| NG |
|
REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here |
| OK |
|
CHECK PRE-HEATING CONTROL CIRCUIT
Check the pre-heating control circuit Click here.
| NG |
|
REPAIR OR REPLACE MALFUNCTIONING PARTS |
| OK |
|
CHECK FUEL QUALITY
Check that fuel with a low cetane number is used.
| NEXT |
|
CHECK ENGINE STARTING CONDITION
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 | Proceed to |
|---|---|
| The engine can be started. | A |
| There is no initial combustion even when the engine can be cranked. | B |
| B |
|
REPLACE INJECTOR ASSEMBLY OF ALL CYLINDERS Click here |
| A |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
| NEXT |
|
END
CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM)
Disconnect the suction control valve connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | ||||||
|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | ||||||
|---|---|---|---|---|---|---|
|
Reconnect the suction control valve connector.
Reconnect the ECM connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP
Disconnect the inlet hose from the fuel supply pump.
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 |
|
REPLACE FUEL SUPPLY PUMP
Replace the fuel supply pump Click here.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
| NEXT |
|
READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.
Start the engine.
Read the Fuel Press value while cranking and idling the engine.
| Result | Proceed to |
|---|---|
| The engine can be started and Fuel Press is 20000 kPa or more. | A |
| The engine cannot be started or the engine can be started but the Fuel Press is less than 20000 kPa during cranking. | B |
| B |
|
INSPECT INJECTOR ASSEMBLY (INSPECTION FOR NOZZLE NEEDLE CLOSING PROBLEM) Click here |
| A |
|
END
INSPECT INJECTOR ASSEMBLY (INSPECTION FOR NOZZLE NEEDLE CLOSING PROBLEM)
Remove the glow plug assembly for all the cylinders Click here.
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 +/-10000 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 | Proceed to |
|---|---|
| No fuel on glow plugs | A |
| Fuel on glow plugs | B |
Install the glow plug assembly Click here.
| B |
|
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER Click here |
| A |
|
REPLACE COMMON RAIL ASSEMBLY
Replace the common rail assembly Click here.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
| NEXT |
|
END
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER
Replace the injector assembly Click here.
| NEXT |
|
PERFORM REGISTRATION AND INITIALIZATION Click here |
REPLACE INJECTOR ASSEMBLY OF ALL CYLINDERS
Replace the injector assemblies Click here.
| NEXT |
|
PERFORM REGISTRATION AND INITIALIZATION
Register the injector compensation code Click here.
Perform Pilot Quantity Learning Values Reset Click here.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
| NEXT |
|
END
CHECK AND REPLACE CLOGGED FUEL PIPE (INCLUDING FUEL FREEZING) (FUEL TANK - FUEL SUPPLY PUMP)
Check and replace the clogged fuel pipe.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM Click here |
ADD FUEL
Add fuel.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
| NEXT |
|
END
CHECK VC OUTPUT CIRCUIT
Check the VC output circuit Click here.
| NEXT |
|
CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
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
CHECK ECM POWER SOURCE CIRCUIT
Check the ECM power source circuit Click here.
| NEXT |
|
CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
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
PERFORM REGISTRATION AND INITIALIZATION
Register the injector compensation code Click here.
Perform Pilot Quantity Learning Values Reset Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
| NEXT |
|
END