check engine NISSAN PICK-UP 2001 Repair Manual

Work Flow
*1 Refer to MA section (ªChecking and
Replacing Fuel Filter and Draining
Waterº, ªENGINE MAINTENANCEº).
*2 If time data of ªSELF-DIAG
RESULTSº is other than ª0º, per-
form ªTROUBLE DIAGNOSIS FOR
INTERMITTENT INCIDENTº,
EC-3470.*3 If the incident cannot be verified,
perform ªTROUBLE DIAGNOSIS
FOR INTERMITTENT INCIDENTº,
EC-3470.
*4 If the on board diagnostic system
cannot be performed, check main
power supply and ground circuit.
Refer to ªTROUBLE DIAGNOSISFOR POWER SUPPLYº, EC-3471.
*5 If malfunctioning part cannot be
detected, perform ªTROUBLE
DIAGNOSIS FOR INTERMITTENT
INCIDENTº, EC-3470.SEF374YC
TROUBLE DIAGNOSIS Ð INTRODUCTIONYD25DDTi
EC-3442

DESCRIPTION FOR WORK FLOW
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using
the ªDIAGNOSTIC WORKSHEETº, EC-3440.
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II) the DTC, then erase the
DTC. Refer to EC-3428.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-3470.
Study the relationship between the cause, specified by DTC, and the symptom described by the customer. (The
ªSymptom Matrix Chartº will be useful. Refer to EC-3451.) Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The ªDIAGNOSTIC WORK SHEETº is useful to verify the incident. Connect CONSULT-II to the vehicle in DATA
MONITOR (AUTO TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-3470.
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the DTC by driving in (or performing) the ªDTC Confirmation Procedureº. Check and read the DTC
by using CONSULT-II.
During the DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO TRIG)
mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-3470.
In case the ªDTC Confirmation Procedureº is not available, perform the ªOverall Function Checkº instead. The
DTC cannot be displayed by this check, however, this simplified ªcheckº is an effective alternative.
The ªNGº result of the ªOverall Function Checkº is the same as the DTC detection.
STEP VTake the appropriate action based on the results of STEP I through IV.
If the malfunction code is indicated, proceed to TROUBLE DIAGNOSIS FOR DTC XXXX.
If the normal code is indicated, proceed to the Basic Inspection, EC-3445. Then perform inspections according to
the Symptom Matrix Chart. Refer to EC-3451.
STEP VIIdentify where to begin diagnosis based on the relationship study between symptom and possible causes.
Inspect the system for mechanical binding, loose connectors or wiring damage using (tracing) ªHarness Layoutsº.
Gently shake the related connectors, components or wiring harness with CONSULT-II set in ªDATA MONITOR
(AUTO TRIG)º mode.
Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CON-
SULT-II. Refer to EC-3464 or EC-3461.
The ªDiagnostic Procedureº in EC section contains a description based on open circuit inspection. A short circuit
inspection is also required for the circuit check in the Diagnostic Procedure. For details, refer to GI section (ªCir-
cuit Inspectionº, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº).
Repair or replace the malfunction parts.
If the malfunctioning part cannot be detected, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENTº, EC-3470.
STEP VIIOnce you have repaired the circuit or replaced a component, you need to run the engine in the same conditions
and circumstances which resulted in the customer's initial complaint.
Perform the ªDTC Confirmation Procedureº and confirm the normal code (DTC No. 0505) is detected. If the inci-
dent is still detected in the final check, perform STEP VI by using a different method from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) DTC in ECM.
(Refer to EC-3428.)
TROUBLE DIAGNOSIS Ð INTRODUCTIONYD25DDTi
Work Flow (Cont'd)
EC-3443

Basic Inspection
Precaution:
Perform Basic Inspection without electrical or mechanical
loads applied;
+Shift lever is in neutral position,
+Heat up switch is OFF,
+Headlamp switch is OFF,
+Air conditioner switch is OFF,
+Rear defogger switch is OFF,
+Steering wheel is in the straight-ahead position, etc.
1 INSPECTION START
1. Check service records for any recent repairs that may indicate a related problem.
2. Check the current need for scheduled maintenance, especially for fuel filter and air cleaner filter. Refer to MA section.
3. Open engine hood and check the following:
+Harness connectors for improper connections
+Vacuum hoses for splits, kinks, or improper connections
+Wiring for improper connections, pinches, or cuts
SEF142I
4. Start engine and warm it up to the normal operating temperature.
cGO TO 2.
2 PREPARATION FOR CHECKING IDLE SPEED
With CONSULT-II
Connect CONSULT-II to the data link connector.
Without CONSULT-II
Install diesel tacho tester to the vehicle.
cGO TO 3.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
EC-3444

3 CHECK IDLE SPEED
With CONSULT-II
1. Select ªCKPSzRPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
2. Read idle speed.
SEF817Y
Without CONSULT-II
Check idle speed.
750 25 rpm
OK or NG
OKcINSPECTION END
NGcGO TO 4.
4 BLEED AIR FROM FUEL SYSTEM
1. Stop engine.
2. Using priming pump, bleed air from fuel system. Refer to ªAir Bleedingº, EC-3426.
cGO TO 5.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
Basic Inspection (Cont'd)
EC-3445

5 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPSzRPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750 25 rpm
OK or NG
OKcINSPECTION END
NGcGO TO 6.
6 DRIN WATER FROM FUEL FILTER
Drain water from fuel filter. Refer to MA section (ªChecking and Replacing Fuel Filter and Draining Waterº, ªENGINE MAINTE-
NANCEº).
cGO TO 7.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
Basic Inspection (Cont'd)
EC-3446

7 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPSzRPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750 25 rpm
OK or NG
OKcINSPECTION END
NGcGO TO 8.
8 CHECK AIR CLEANER FILTER
Check air cleaner filter for clogging or breaks.
OK or NG
OKcGO TO 9.
NGcReplace air cleaner filter.
9 CHECK FUEL INJECTION NOZZLE
Check fuel injection nozzle opening pressure. Refer to ªInjection pressure testº, EC-3418.
OK or NG
OKcGO TO 10.
NGcReplace fuel injection nozzle assembly.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
Basic Inspection (Cont'd)
EC-3447

10 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPSzRPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750 25 rpm
OK or NG
OKcINSPECTION END
NGcGO TO 11.
11 CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM section, ªMEASUREMENT OF COMPRESSION PRESSUREº.
OK or NG
OKcGO TO 12.
NGcFollow the instruction of ªMEASUREMENT OF COMPRESSION PRESSUREº.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
Basic Inspection (Cont'd)
EC-3448

12 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPSzRPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750 25 rpm
OK or NG
OKcINSPECTION END
NGcReplace electronic control fuel injection pump.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD25DDTi
Basic Inspection (Cont'd)
EC-3449

Symptom Matrix Chart
SYSTEM Ð Basic engine control sys-
temSYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
Electronic control fuel injection pump
mainframe4444444445544 Ð *1
Injection nozzle3333333334433EC-3415 *2
Glow system1111 1EC-3622
Engine body3333333 344 3 EMsection *3
EGR system3 3 EC-3606
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD25DDTi
EC-3450

SYSTEM Ð Basic engine control sys-
temSYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT-II?
Fuel cutBLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
Electronic control fuel injection pump
mainframe443 4 54 333 Ð *1
Injection nozzle 3 3 3 4 3 1 EC-3415 *2
Glow system 1 EC-3622
Engine body 3 3 3 3 3 3 EM section *3
EGR system 3 EC-3606
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD25DDTi
Symptom Matrix Chart (Cont'd)
EC-3451