2004 NISSAN TERRANO Service Repair Manual

Introduction
The engine has an ECM to control major systems such as fuel
injection control, fuel injection timing control, glow control system,
etc. The ECM accepts input signals from sensors and instantly
drives electronic control fuel injection pump. It is essential that both
input and output signals are proper and stable. At the same time,
it is important that there are no problems such as vacuum leaks,
or other problems with the engine.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this
case, careful checking of suspected circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems. A road
test with CONSULT-II or a circuit tester connected should be per-
formed. Follow the ªWork Flowº, EC-48.
Before undertaking actual checks, take a few minutes to talk with
a customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such problems, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A ªDiagnostic Worksheetº like the
example on next page should be used.
Start your diagnosis by looking for ªconventionalº problems first.
This will help troubleshoot driveability problems on an electronically
controlled engine vehicle.
DIAGNOSTIC WORKSHEET
There are many operating conditions that lead to the malfunction
of engine components. A good grasp of such conditions can make
troubleshooting faster and more accurate.
In general, each customer feels differently about a problem. It is
important to fully understand the symptoms or conditions for a
customer complaint.
Utilize a diagnostic worksheet like the one shown below in order to
organize all the information for troubleshooting.
SEF858S
SEF233G
SEF234G
SEF907L
TROUBLE DIAGNOSIS Ð INTRODUCTIONZD30DDTi
EC-46
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Worksheet sample
MTBL0397
TROUBLE DIAGNOSIS Ð INTRODUCTIONZD30DDTi
Introduction (Cont'd)EC-47
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Work Flow
*1 Refer to MA section (ªCheckingand Replacing Fuel Filter and
Draining Waterº, ªENGINE MAIN-
TENANCEº).
*2 If time data of ªSELF-DIAG RESULTSº is other than ª0º, per-
form ªTROUBLE DIAGNOSIS
FOR INTERMITTENT INCIDENTº,
EC-78. *3 If the incident cannot be verified,
perform ªTROUBLE DIAGNOSIS
FOR INTERMITTENT INCIDENTº,
EC-78.
*4 If the on board diagnostic system cannot be performed, check main
power supply and ground circuit.
Refer to ªTROUBLE DIAGNOSIS
FOR POWER SUPPLYº, EC-79. *5 If malfunctioning part cannot be
detected, perform ªTROUBLE
DIAGNOSIS FOR INTERMIT-
TENT INCIDENTº, EC-78.
YEC253A
TROUBLE DIAGNOSIS Ð INTRODUCTIONZD30DDTi
EC-48
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DESCRIPTION FOR WORK FLOW
STEPDESCRIPTION
STEP I Get detailed information about the conditions and the environment when the incident/symptom occurred using
the ªDIAGNOSTIC WORKSHEETº, EC-46.
STEP II Before confirming the concern, check and write down (print out using CONSULT-II) the DTC, then erase the
DTC. Refer to EC-33.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-78.
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-56.) Also check related service bulletins for information.
STEP III Try 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-78.
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IV Try 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-78.
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 V Take 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-50. Then perform inspections according to
the Symptom Matrix Chart. Refer to EC-56.
STEP VI Identify 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-69 or EC-66.
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-78.
STEP VII Once 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-33.)
TROUBLE DIAGNOSIS Ð INTRODUCTIONZD30DDTi
Work Flow (Cont'd)
EC-49
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Basic Inspection
Precaution:
Perform Basic Inspection without electrical or mechanical
loads applied;
IShift lever is in neutral position,
I Heat up switch is OFF,
I Headlamp switch is OFF,
I Air conditioner switch is OFF,
I Rear defogger switch is OFF,
I 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:
IHarness connectors for improper connections
I Vacuum hoses for splits, kinks, or improper connections
I Wiring for improper connections, pinches, or cuts
SEF142I
4. Start engine and warm it up to the normal operating temperature.
EGO 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.
EGO TO 3.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONZD30DDTi
EC-50
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3 CHECK IDLE SPEED
With CONSULT-II
1. Select ªCKPS×RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
2. Read idle speed.
SEF817Y750 25 rpm
Without CONSULT-II
Check idle speed. 750 25 rpm
OK or NG
OK EINSPECTION END
NG EGO TO 4.
4 CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK EGO TO 5.
NG ERepair or replace.
5 BLEED AIR FROM FUEL SYSTEM
1. Stop engine.
2. Using priming pump, bleed air from fuel system. Refer to ªAir Bleedingº, EC-32.
EGO TO 6.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONZD30DDTi
Basic Inspection (Cont'd)
EC-51
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6 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS×RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y750 25 rpm
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed. 750 25 rpm
OK or NG
OK EINSPECTION END
NG EGO TO 7.
7 DRAIN WATER FROM FUEL FILTER
Drain water from fuel filter. Refer to MA section (ªChecking and Replacing Fuel Filter and Draining Waterº, ªENGINE MAINTE-
NANCEº).
EGO TO 8.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONZD30DDTi
Basic Inspection (Cont'd)
EC-52
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8 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS×RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y750 25 rpm
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed. 750 25 rpm
OK or NG
OK EINSPECTION END
NG EGO TO 9.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONZD30DDTi
Basic Inspection (Cont'd)
EC-53
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