DESCRIPTION
Faults and Symptoms of Common Rail Diesel Components
Engine Control
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. |
Symptom and Corresponding Main Fault |
|
Data List | MAP |
Main fault |
|
Symptoms | Lack of power (when vehicle is starting, under heavy load) (Black smoke is not emitted when racing while vehicle is stopped) |
Data List | MAP
|
Main fault | Blockage |
Symptoms | Lack of power (high engine speed, under heavy load) |
Main fault | Glow system malfunction |
Symptoms | Difficult to start, rough idle, knocking, white smoke (when cold) |
Data List | Check the glow plug indicator light |
Diagnostic Point | Measure the resistance of the glow plug |
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. |
Main fault | Damaged, seized up |
Symptoms | Cannot crank, crank speed is low, strange noise |
Main fault | Loss of compression |
Symptoms | Rough idle (lack of power always) |
Data List | Engine Speed of Cyl
Injection Feedback Val
|
Main fault | Starter system malfunction |
Symptoms | Difficult to start |
Data List | Starter Signal
|
Diesel Injection
Main fault | - |
Symptoms | Difficult to start, engine stalling, rough idle, lack of power |
Data List | Common Rail Pressure, Target Common Rail Pressure, Target Pump SCV Current
Tech Tips
|
Diagnostic Trouble Code | Even if Common Rail Pressure is below Target Common Rail Pressure, a DTC will not be stored. |
Main fault | Blockage |
Symptoms | Difficult to start, engine stalling, rough idle, lack of power |
Data List | Common Rail Pressure, Target Common Rail Pressure
Tech Tips The fuel pressure changes at engine start, but is approx. 25000 kPa at engine start after the engine is warmed up. |
Diagnostic Trouble Code | Even if Common Rail Pressure is below Target Common Rail Pressure, a DTC will not be stored. |
Main fault | Blockage |
Symptoms | Rough idle, lack of power, black smoke, white smoke, knocking |
Data List | Injection Feedback Val
|
Main fault | Does not completely close |
Symptoms | Difficult to start, engine stall, rough idle, lack of power |
Main fault | Circuit fault: The injector assembly does not open. |
Symptoms | Difficult to start, rough idle, lack of power, black smoke, white smoke, knocking |
Data List | Same as injector assembly |
Diagnostic Trouble Code | When the injector driver has a fault, some DTCs may be stored. |
Main fault | Open circuit, decrease in performance (foreign matter is stuck) |
Symptoms | Difficult to start, rough idle, engine stall, lack of power |
Data List | Common Rail Pressure, Target Common Rail Pressure
|
Diagnostic Trouble Code | When the fuel pressure sensor has a fault, some DTCs may be stored. |
Main fault | - |
Symptoms | Difficult to start, rough idle (especially when cold) |
Diesel EGR
Main fault |
|
Symptoms |
|
Data List | Actual EGR Valve Pos, Actual EGR Valve Pos #2, Target EGR Valve Pos, Target EGR Valve Pos #2
EGR Close Lrn. Val., EGR Close Lrn. Val. #2
|
Diesel Throttle
Main fault | Stuck, does not move smoothly |
Symptoms |
|
Data List |
|
Data List Related to Starting Trouble
MAP
MAF
Intake Air
Coolant Temp
Battery Voltage
Starter Signal
Engine Speed of Cyl #1 (to #8)
Target Common Rail Pressure
Common Rail Pressure
Target Pump SCV Current
Injection Feedback Val #1 (to #8)
Injection Volume
Actual Throttle Position
Actual Throttle Position #2
Target EGR Valve Pos.
Target EGR Valve Pos #2
Actual EGR Valve Pos
Actual EGR Valve Pos #2
EGR Close Lrn. Val.
EGR Close Lrn. Val #2
CAUTION / NOTICE / HINT
Explanation of Symptom
Starting Trouble | For good starting it is essential to have:
The fuel is ignited by the heat which is generated by compression pressure. With problems such as a depleted battery, the crankshaft speed can become low, or if the engine compression is poor due to leakage, 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 injector assembly is open. |
Trouble Area Chart According to Problem Cause
Note
After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.
After replacing the fuel supply pump assembly, the ECM needs initialization Click here.
After replacing an injector assembly, 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
CHECK ENGINE CRANKING CONDITION
Check the engine cranking condition.
Result | Proceed to |
---|---|
Cranking is OK. | 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 |
Does not crank at all. | C |
B |
CHECK BATTERY CONDITION Click here |
C |
READ OUTPUT DTC (RELATED TO ENGINE) Click here |
A |
READ ALL OUTPUT DTCS
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Utility / All Codes.
Result | Proceed to |
---|---|
No DTC is output | A |
Engine related DTCs are output | B |
Tech Tips
If only DTC P1604 is output, proceed to step 3.
B |
GO TO RELATED DTC Click here |
A |
TAKE SNAPSHOT DURING STARTING AND IDLING (PROCEDURE 3)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Engine and ECT / Data List / All Data.
Take a snapshot when idling with no load after the engine is warmed up and when starting trouble is occurring.
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 is 70°C (158°F) or higher) 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.
Take a snapshot when the problem is occurring, such as when the engine is cold. However, if the problem does not reoccur, it is acceptable to only take a snapshot after the engine is warmed up and when the engine is started.
NEXT |
CHECK SNAPSHOT (COMMON RAIL PRESSURE)
Check Common Rail Pressure in the snapshot taken in procedure 3 when the engine was started.
Result | Proceed to |
---|---|
At the point in the illustration labeled "a", Common Rail Pressure is less than 10000 kPa from the value of Common Rail Pressure when cranking starts | A |
At the point in the illustration labeled "c", Common Rail Pressure is below Target Common Rail Pressure by 15000 kPa or more | B |
Common Rail Pressure increases to a value that is higher than Target Common Rail Pressure immediately after cranking, and, at the point in the illustration labeled "d", Common Rail Pressure is higher than Target Common Rail Pressure | C |
Except above | D |
Tech Tips
Even if Common Rail Pressure is temporarily higher than Target Common Rail Pressure, as shown at the point in the illustration labeled "b", the fuel supply pump assembly is normal.
Common Rail Pressure is about 25000 to 35000 kPa when the engine is cranking and the engine coolant temperature is 0°C (32°F) or higher.
Common Rail Pressure increases rapidly during cranking.
B |
READ VALUE USING GTS (COMMON RAIL PRESSURE) Click here |
C |
INSPECT INJECTOR DRIVER Click here |
D |
INSPECT INJECTOR ASSEMBLY (CHECKING FOR PRESENCE OF AIR) Click here |
A |
CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP ASSEMBLY
Disconnect the inlet hose from the fuel supply pump assembly.
Operate the priming pump and check that fuel is being supplied to the fuel supply pump assembly.
OK |
---|
Fuel is properly supplied to the fuel supply pump assembly 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).
Reconnect the inlet hose.
NG |
CHECK AND REPAIR OR REPLACE CLOGGED FUEL PIPE (INCLUDING FROZEN FUEL) (FUEL TANK - FUEL SUPPLY PUMP) Click here |
OK |
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 | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Standard Resistance | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Reconnect the suction control valve connector.
Reconnect the ECM connector.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)
Replace the supply pump assembly Click here.
NEXT |
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
Perform PM forced regeneration Click here.
Tech Tips
When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.
NEXT |
PERFORM SUPPLY PUMP INITIALIZATION
Perform supply pump initialization Click here.
NEXT |
READ VALUE USING GTS (COMMON RAIL PRESSURE)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Engine and ECT / Data List / Common Rail Pressure.
Start the engine.
Read the Fuel Press values while cranking and idling the engine.
Result | Proceed to |
---|---|
The engine cannot be started or the engine can be started but Common Rail Pressure is below 20000 kPa 2 seconds after the starter signal changes from OFF to ON | B |
Except above | A |
A |
END |
B |
INSPECT INJECTOR ASSEMBLY (INSPECTION FOR VALVE 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 an injector assembly.
After replacing an injector assembly, make sure that the common rail 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.
Install the glow plug assembly Click here.
NEXT |
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER Click here |
CHECK AND REPAIR OR REPLACE CLOGGED FUEL PIPE (INCLUDING FROZEN FUEL) (FUEL TANK - FUEL SUPPLY PUMP)
Check and repair or replace the clogged fuel pipe.
NEXT |
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
Perform PM forced regeneration Click here.
Tech Tips
When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.
NEXT |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
READ VALUE USING GTS (COMMON RAIL PRESSURE)
Check Common Rail Pressure in the snapshot taken in procedure 3 when the engine was warmed up.
Result | Proceed to |
---|---|
Difference between Common Rail Pressure and Target Common Rail Pressure is 5000 kPa (51.0 kgf/cm2, 725 psi) or more |
A |
Except above | B |
B |
REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS Click here |
A |
REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)
Replace the fuel supply pump assembly Click here.
NEXT |
PERFORM SUPPLY PUMP INITIALIZATION
Perform supply pump initialization Click here.
NEXT |
REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS
Replace the injector assemblies Click here.
Note
When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe.
Follow the procedure in the repair manual and temporarily install the injection pipes and nozzle leakage pipe, and then correctly position the injector assemblies. After that, tighten parts according to the torque specifications.
If the installation procedure is not performed correctly, injector assemblies may become out of position, which may cause the injector assemblies to deteriorate, resulting in malfunctions.
If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.
If an injector assembly becomes out of position, it is possible that the seal between the injector assembly and injection pipe may become incomplete, resulting in a fuel leak.
NEXT |
CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER Click here |
INSPECT INJECTOR ASSEMBLY (CHECKING FOR PRESENCE OF AIR)
When the engine does not start, perform the following procedure.
Stop the engine and leave the vehicle for 4 hours or more.
Tech Tips
It is necessary to leave the vehicle for 4 hours or more to wait for air in the injector assembly to come out.
Check that the engine starts.
OK |
---|
The engine starts. |
When the engine starts, perform the following procedure.
Bleed the air from the fuel system Click here.
Check that the engine starts.
OK |
---|
The engine starts. |
OK |
END |
NG |
CHECK DATA LIST
Check Injection Feedback Val # in the snapshot taken in procedure 3 when the engine was idling.
Result | Proceed to |
---|---|
Injection Feedback Val #1 to #8 are 3 mm3/st or less. Injection Volume is more than 13 mm3/st. |
A* |
Injection Feedback Val for at least one cylinder is more than +3 mm3/st Tech Tips There may be a malfunction in the corresponding cylinder. |
B |
Except above | C |
Tech Tips
*: When this case occurs, usually symptoms may be noticeable, such as difficulty starting or lack of power.
The shift lever should be in neutral and the A/C switch and all accessory switches should be off.
B |
PERFORM ACTIVE TEST USING GTS (CHECK THE CYLINDER COMPRESSION) Click here |
C |
CHECK TEMPERATURE WHEN STARTING TROUBLE OCCURS Click here |
A |
REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS
Replace the injector assemblies Click here.
Note
When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe.
Follow the procedure in the repair manual and temporarily install the injection pipes and nozzle leakage pipe, and then correctly position the injector assemblies. After that, tighten parts according to the torque specifications.
If the installation procedure is not performed correctly, injector assemblies may become out of position, which may cause the injector assemblies to deteriorate, resulting in malfunctions.
If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.
If an injector assembly becomes out of position, it is possible that the seal between the injector assembly and injection pipe may become incomplete, resulting in a fuel leak.
NEXT |
CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER Click here |
PERFORM ACTIVE TEST USING GTS (CHECK THE CYLINDER COMPRESSION)
Tech Tips
Use this Active Test to help determine whether a cylinder has compression loss or not.
Connect the GTS to the DLC3.
Start the engine and turn the GTS on.
Enter the following menus: Engine and ECT / Active Test / Check the Cylinder Compression / Data List / Compression / Engine Speed of Cyl #1 to #8.
Check the engine speed during the Active Test.
Result | Proceed to |
---|---|
Except below | A |
The values of Engine Speed Cyl #1 to #8 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.
B |
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER Click here |
A |
CHECK CYLINDER COMPRESSION PRESSURE OF MALFUNCTIONING CYLINDER
Tech Tips
Measure the compression of the cylinder that had a high speed during the "Check the Cylinder Compression" Active Test.
Check the cylinder compression pressure Click here.
NG |
CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION |
OK |
REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER
Tech Tips
It can be determined that the injector assembly is faulty as the corresponding cylinder is malfunctioning, but has no compression loss.
Replace the injector assembly Click here.
Note
When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe.
Follow the procedure in the repair manual and temporarily install the injection pipes and nozzle leakage pipe, and then correctly position the injector assemblies. After that, tighten parts according to the torque specifications.
If the installation procedure is not performed correctly, injector assemblies may become out of position, which may cause the injector assemblies to deteriorate, resulting in malfunctions.
If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.
If an injector assembly becomes out of position, it is possible that the seal between the injector assembly and injection pipe may become incomplete, resulting in a fuel leak.
NEXT |
CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER
Clean the fuel filter case and replace the fuel filter.
Tech Tips
Be sure to clean the inside of the fuel filter case as the fuel injectors may not operate properly if the fuel filter is installed with foreign matter remaining inside the fuel filter case.
NEXT |
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
Perform PM forced regeneration Click here.
Tech Tips
When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.
NEXT |
REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING
Register the injector compensation codes Click here.
Perform the injector pilot quantity learning Click here.
NEXT |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
NEXT |
END |
INSPECT INJECTOR DRIVER
Even in cases where DTC P062D and P062E are not stored even though the engine cannot be started, perform the DTC P062D troubleshooting procedure Click here.
Tech Tips
When the engine cannot be started due to a malfunction in the injector driver system, once the DTCs are cleared, the system cannot store DTC P062D and P062E even if it is confirmed that the engine cannot be started when trying to reproduce the problem symptoms.
As DTC P062D and P062E cannot be stored when starting the engine, fuel injection signals are output by the ECM, but fuel is not actually injected. Therefore, an excessive amount of fuel is supplied to the common rail by the fuel supply pump assembly, and as a result, the fuel pressure is higher than the target common rail pressure in the data recorded at the time the engine was having trouble starting.
If the problem cannot be determined even after performing the DTC P062D and P062E troubleshooting procedure and the fuel pressure is higher than the target common rail pressure when attempting to start the engine, proceed to the next step.
Result | Proceed to |
---|---|
Injector driver (EDU) circuit is normal | A |
Injector driver (EDU) circuit is abnormal | B |
B |
REPAIR OR REPLACE MALFUNCTIONING PARTS |
A |
INSPECT INJECTOR ASSEMBLY (CHECKING FOR PRESENCE OF AIR)
When the engine does not start, perform the following procedure.
Stop the engine and leave the vehicle for 4 hours or more.
Tech Tips
It is necessary to leave the vehicle for 4 hours or more to wait for air in the injector assembly to come out.
Confirm the engine starts.
When the engine starts, perform the following procedure.
Bleed the air from the fuel system Click here.
Confirm the engine starts.
NEXT |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 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 |
READ VALUE USING ENGINE COOLANT TEMPERATURE SENSOR (COOLANT TEMP)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Engine and ECT / Data List / All Data / Coolant Temp.
Read the value displayed on the GTS.
OK |
---|
Coolant Temp is not high when the engine is cold, and not low after the engine is warmed up |
NG |
INSPECT ENGINE COOLANT TEMPERATURE SENSOR Click here |
OK |
INSPECT GLOW PLUG (RESISTANCE)
Inspect the glow plug Click here.
NG |
REPLACE GLOW PLUG Click here |
OK |
CHECK FUEL QUALITY
Check that only diesel fuel is being used.
Check that the fuel does not contain any impurities.
NEXT |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
READ OUTPUT DTC (RELATED TO ENGINE)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Engine and ECT / Trouble Codes.
Read the DTCs.
Result | Proceed to |
---|---|
No DTC is output | A |
Engine related DTCs are output | B |
B |
GO TO RELATED DTC Click here |
A |
CHECK COMMUNICATION BETWEEN GTS AND ECM
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Check if the normal starting screen appears (check whether communication with the ECM is possible).
Tech Tips
Use a GTS that is able to communicate with other vehicles.
OK |
---|
Communication is possible (vehicle can be recognized). |
NG |
CHECK VC OUTPUT CIRCUIT Click here |
OK |
READ VALUE USING GTS (STARTER SIGNAL AND NEUTRAL POSITION SW SIGNAL)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Engine and ECT / Data List / All Data / Starter Signal and Neutral Position SW Signal.
Read the value displayed on the GTS.
OK | |||||||||
---|---|---|---|---|---|---|---|---|---|
|
NG |
INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY |
OK |
CHECK STARTING SYSTEM
Inspect the starting system.
Tech Tips
Be sure to inspect the following areas:
Starter relay
Starter assembly
Immobiliser system
NEXT |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
NEXT |
END |