NISSAN PICK-UP 2001 Repair Manual

Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
ACCEL POS SEN [V]
jj+The accelerator position sensor signal
voltage is displayed.
FULL ACCEL SW
[ON/OFF]jj+Indicates [ON/OFF] condition from the
accelerator position switch signal.
OFF ACCEL SW
[ON/OFF]jj+Indicates [ON/OFF] condition from the
accelerator position switch signal.
SPILL/V [ÉCA]
j+The control position of spill valve (sent
from electronic control fuel injection
pump) is displayed.
BATTERY VOLT [V]
jj+The power supply voltage of ECM is dis-
played.
I/C INT/A T/S [V]
jj+The signal voltage of the intake air tem-
perature sensor is displayed.
P/N POSI SW
[ON/OFF]jj+Indicates [ON/OFF] condition from the
park/neutral position switch signal.
START SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition from the
starter signal.+After starting the engine, [OFF] is dis-
played regardless of the starter signal.
AIR COND SIG
[ON/OFF]jj+Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
BRAKE SW [ON/OFF]
jj+Indicates [ON/OFF] condition from the
stop lamp switch signal.
BRAKE SW2
[ON/OFF]jj+Indicates [ON/OFF] condition from the
brake pedal position switch.
IGN SW
[ON/OFF]jj+Indicates [ON/OFF] condition from igni-
tion switch signal.
WARM UP SW
[ON/OFF]j+Indicates [ON/OFF] condition from the
heat up switch signal.
TURBO BST SEN
[kPa]j+The charge air pressure (determined by
the signal voltage sent to the ECM) is
displayed.
DECELER F/CUT
[ON/OFF]j+The [ON/OFF] condition from decelera-
tion fuel cut signal (sent from ECM) is
displayed.
INJ TIMG C/V [%]
j+The duty ratio of fuel injection timing
control valve (sent from electronic con-
trol fuel injection pump) is displayed.
AIR COND RLY
[ON/OFF]j+Indicates the control condition of the air
conditioner relay (determined by ECM
according to the input signals).
GLOW RLY [ON/OFF]
j+The glow relay control condition (deter-
mined by ECM according to the input
signal) is displayed.
COOLING FAN
[ON/OFF]
j+Indicates the control condition of the
cooling fans (determined by ECM
according to the input signal).
+ON ... Operates.
OFF ... Stopped.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD25DDTi
CONSULT-II (Cont'd)
EC-3436

Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
EGR VOL CON/V
[step]
j+Indicates the EGR volume control value
computed by the ECM according to the
input signals.
+The opening becomes larger as the
value increases.
BARO SEN [kPa]
j+The barometric pressure (determined by
the signal voltage from the barometric
pressure sensor built into the ECM) is
displayed.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
COOLING FAN+Ignition switch: ON
+Turn cooling fan ªONº and ªOFFº
using CONSULT-II.Cooling fan moves and stops.+Harness and connector
+Cooling fan motor
+Cooling fan relay
OFF ACCEL PO
SIG+Clears the self-learning fully closed accelerator position, detected by accelerator position sensor, from the
ECM.
GLOW RLY+Ignition switch: ON (Engine
stopped)
+Turn the glow relay ªONº and
ªOFFº using CONSULT-II and
listen to operating sound.Glow relay makes the operating
sound.+Harness and connector
+Glow relay
INJ TIMING*1+Engine: Return to the original
trouble condition
+Retard the injection timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.+Electronic control fuel injection
pump
EGR VOL CONT/V+Ignition switch: ON
+Change EGR volume control
valve opening step using CON-
SULT-II.EGR volume control valve makes
an operating sound.+Harness and connector
+EGR volume control valve
*1: When using this item, DTC 0707 ªP7zF/INJ TIMG FBº may be detected. If so, erase it because it is not a malfunction.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD25DDTi
CONSULT-II (Cont'd)
EC-3437

REAL TIME DIAGNOSIS IN DATA MONITOR MODE
CONSULT-II has two kinds of triggers and they can be selected
by touching ªSETTINGº in ªDATA MONITORº mode.
1) ªAUTO TRIGº (Automatic trigger):
+The malfunction will be identified on the CONSULT-II screen
in real time.
In other words, DTC will be displayed if the malfunction is
detected by ECM.
At the moment a malfunction is detected by ECM, ªMONI-
TORº in ªDATA MONITORº screen is changed to ªRecording
Data ... xx%º as shown at left, and the data after the mal-
function detection is recorded. Then when the percentage
reached 100%, ªREAL-TIME DIAGº screen is displayed. If
ªSTOPº is touched on the screen during ªRecording Data ...
xx%º, ªREAL-TIME DIAGº screen is also displayed.
The recording time after the malfunction detection and the
recording speed can be changed by ªTRIGGER POINTº and
ªRecording Speedº. Refer to CONSULT-II OPERATION
MANUAL.
2) ªMANU TRIGº (Manual trigger):
+DTC will not be displayed automatically on CONSULT-II
screen even though a malfunction is detected by ECM.
DATA MONITOR can be performed continuously even
though a malfunction is detected.
Use these triggers as follows:
1) ªAUTO TRIGº
+While trying to detect the DTC by performing the ªDTC Con-
firmation Procedureº, be sure to select to ªDATA MONITOR
(AUTO TRIG)º mode. You can confirm the malfunction at the
moment it is detected.
+While narrowing down the possible causes, CONSULT-II
should be set in ªDATA MONITOR (AUTO TRIG)º mode,
especially in case the incident is intermittent.
When you are inspecting the circuit by gently shaking (or
twisting) the suspicious connectors, components and har-
ness in the ªDTC Confirmation Procedureº, the moment a
malfunction is found the DTC will be displayed. (Refer to GI
section, ªIncident Simulation Testsº in ªHOW TO PERFORM
EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCI-
DENTº.)
2) ªMANU TRIGº
+If the malfunction is displayed as soon as ªDATA MONITORº
is selected, reset CONSULT-II to ªMANU TRIGº. By select-
ing ªMANU TRIGº you can monitor and store the data. The
data can be utilized for further diagnosis, such as a compari-
son with the value for the normal operating condition.
SEF373Y
SEF707X
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD25DDTi
CONSULT-II (Cont'd)
EC-3438

FUNCTION TEST
This mode is used to inform customers of their vehicle condition of periodic maintenance.
SEF720X
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD25DDTi
CONSULT-II (Cont'd)
EC-3439

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 essen-
tial 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 inter-
mittently 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 performed. Follow the ªWork Flowº, EC-3443.
Before undertaking actual checks, take a few minutes to talk with
a customer who approaches with a driveability complaint. The
customer 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 electroni-
cally 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 INTRODUCTIONYD25DDTi
EC-3440

Worksheet sample
MTBL0397
TROUBLE DIAGNOSIS Ð INTRODUCTIONYD25DDTi
Introduction (Cont'd)
EC-3441

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