
due to receiving external noise, degraded operation of ICs,
etc.
I Keep ECM parts and harnesses dry.
I Before replacing ECM, perform Terminals and Reference
Value inspection and make sure ECM functions properly.
Refer to EC-69.
I If MI illuminates or blinks irregularly when engine is
running, water may have accumulated in fuel filter. Drain
water from fuel filter. If this does not correct the problem,
perform specified trouble diagnostic procedures.
I After performing each TROUBLE DIAGNOSIS, perform
ªDTC Confirmation Procedureº or ªOverall Function
Checkº.
The DTC should not be displayed in the ªDTC Confirmation
Procedureº if the repair is completed. The ªOverall Func-
tion Checkº should be a good result if the repair is com-
pleted.
I When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
I Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the
ECM's transistor. Use a ground other than ECM terminals,
such as the ground.
MEF040D
SAT652J
SEF348N
PRECAUTIONSZD30DDTi
Precautions (Cont'd)
EC-10
http://vnx.su/  

DTC and MI Detection Logic
When a malfunction is detected, the malfunction (DTC) is stored in the ECM memory.
The MI will light up each time the ECM detects malfunction. For diagnostic items causing the MI to light up,
refer to ªTROUBLE DIAGNOSIS Ð INDEXº, EC-7.
Diagnostic Trouble Code (DTC)
HOW TO READ DTC
The DTC can be read by the following methods.
Without CONSULT-II
ECM displays the DTC by a set of four digit numbers with MI illumination in the diagnostic test mode II (Self-
diagnostic results). Example: 0102, 0407, 1004, etc.
With CONSULT-II
CONSULT-II displays the DTC in ªSELF-DIAG RESULTSº mode. Examples: ªCRANK POS SEN (TDC)º, etc.
I Output of the trouble code means that the indicated circuit has a malfunction. However, in the Mode
II it does not indicate whether the malfunction is still occurring or occurred in the past and returned
to normal.
CONSULT-II can identify them. Therefore, using CONSULT-II (if available) is recommended.
HOW TO ERASE DTC
How to erase DTC (
With CONSULT-II)
1. If the ignition switch stays ªONº after repair work, be sure to turn ignition switch ªOFFº once. Wait at least
5 seconds and then turn it ªONº (engine stopped) again.
2. Touch ªENGINEº.
3. Touch ªSELF-DIAG RESULTSº.
4. Touch ªERASEº. (The DTC in the ECM will be erased.)
The emission related diagnostic information in the ECM can be erased by selecting ªERASEº in the ªSELF-
DIAG RESULTSº mode with CONSULT-II.
How to erase DTC (Without CONSULT-II)
1. If the ignition switch stays ªONº after repair work, be sure to turn ignition switch ªOFFº once. Wait at least 5 seconds and then turn it ªONº (engine stopped) again.
2. Change the diagnostic test mode from Mode II to Mode I by using the data link connector. (See EC-36.)
The emission related diagnostic information in the ECM can be erased by changing the diagnostic test mode.
SEF371Y
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
EC-33
http://vnx.su/  

IIf the battery is disconnected, the emission-related diagnostic information will be lost after approx.
24 hours.
I Erasing the emission-related diagnostic information using CONSULT-II is easier and quicker than
switching the diagnostic test mode using the data link connector.
NATS (Nissan Anti-Theft System)
IIf the security indicator lights up with the ignition switch in
the ªONº position or ªNATS MALFUNCTIONº is displayed
on ªSELF-DIAG RESULTSº screen, perform self-diagnostic
results mode with CONSULT-II using NATS program card.
Refer to ªNATS (Nissan Anti-Theft System)º in EL section.
I Confirm no self-diagnostic results of NATS is displayed
before touching ªERASEº in ªSELF-DIAG RESULTSº mode
with CONSULT-II.
I When replacing ECM, initialization of NATS system and
registration of all NATS ignition key IDs must be carried out
with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner.
Regarding the procedures of NATS initialization and NATS
ignition key ID registration, refer to CONSULT-II operation
manual, NATS.
Malfunction Indicator (MI)
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
I If the MI does not light up, refer to EL section (ªWARNING
LAMPS AND CHIMEº) or see EC-310.
2. When the engine is started, the MI should go off. If the MI remains on, the on board diagnostic system has
detected an engine system malfunction.
If MI illuminates or blinks irregularly after starting engine,
water may have accumulated in fuel filter. Drain water from
fuel filter. Refer to MA section.
SEF252Z
SAT652J
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
Diagnostic Trouble Code (DTC) (Cont'd)
EC-34
http://vnx.su/  

Relationship between MI, DTC, CONSULT-II and driving patterns
*1: When a malfunction is detected,MI will light up.
*2: MI will not light up after ignition switch is turned OFF.
*3: When a malfunction is detected for the first time, the DTC will be
stored in ECM. *4: The DTC will not be displayed any
longer after vehicle is driven 40
times without the same malfunc-
tion. (The DTC still remain in
ECM.) *5: Other screens except SELF-DIAG-
NOSTIC RESULTS & DATA
MONITOR (AUTO TRIG) cannot
display the malfunction. DATA
MONITOR (AUTO TRIG) can dis-
play the malfunction at the
moment it is detected.
PBIB0589E
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
Malfunction Indicator (MI) (Cont'd)
EC-38
http://vnx.su/  

ENGINE CONTROL COMPONENT PARTS/CONTROL
SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
SELF-DIAG RESULTS DATA MONI-
TOR ACTIVE
TEST
ENGINE CONTROL COMPONENT PARTS
INPUT Engine coolant temperature sensor X X
Vehicle speed sensor X X
Accelerator position sensor X X X
Accelerator position switch X X
Accelerator switch (F/C) X X
Crankshaft position sensor (TDC) X X
Ignition switch (start signal) X
Park/Neutral position (PNP) switch X
Battery voltage X
Air conditioner switch X
Mass air flow sensor X X
Stop lamp switch X X
Heat up switch X
Charge air pressure sensor X
OUTPUT Glow relay
XX
EGR volume control valve X X X
Cooling fan relay X X X
Air conditioner relay X
Variable nozzle turbocharger control solenoid valve X
Swirl control valve control solenoid valve X X
X: Applicable
SELF-DIAGNOSTIC MODE
Regarding items detected in ªSELF-DIAG RESULTSº mode,
refer to ªTROUBLE DIAGNOSIS Ð INDEXº, EC-7.
DATA MONITOR MODE
Monitored item
[Unit] ECM
input
signals Main
signals Description Remarks
CKPS×RPM (TDC)
[rpm] qqI
The engine speed computed from the
crankshaft position sensor (TDC) signal
is displayed.
CMPS×RPM×PUMP
[rpm] qqI
The engine speed computed from the
pulse signal sent from electronic control
fuel injection pump is displayed.
COOLAN TEMP/S
[ÉC] or [ÉF] qqI
The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is displayed. I
When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine cool-
ant temperature determined by the ECM
is displayed.
VHCL SPEED SE
[km/h] or [mph] qqI
The vehicle speed computed from the
vehicle speed sensor signal is displayed.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
CONSULT-II (Cont'd)
EC-40
http://vnx.su/  
![NISSAN TERRANO 2004  Service Repair Manual Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
FUEL TEMP SEN
[ÉC] or [ÉF] qqI
The fuel temperature (sent from elec-
tronic control fuel injection pump) is dis-
played.
ACCEL NISSAN TERRANO 2004  Service Repair Manual Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
FUEL TEMP SEN
[ÉC] or [ÉF] qqI
The fuel temperature (sent from elec-
tronic control fuel injection pump) is dis-
played.
ACCEL](/manual-img/5/57394/w960_57394-315.png)
Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
FUEL TEMP SEN
[ÉC] or [ÉF] qqI
The fuel temperature (sent from elec-
tronic control fuel injection pump) is dis-
played.
ACCEL POS SEN [V] qqI
The accelerator position sensor signal
voltage is displayed.
FULL ACCEL SW
[ON/OFF] qqI
Indicates [ON/OFF] condition from the
accelerator position switch signal.
ACCEL SW (FC)
[OPEN/CLOSE] qqI
Indicates [OPEN/CLOSE] condition from
the accelerator switch (FC) signal.
OFF ACCEL SW
[ON/OFF] qqI
Indicates [ON/OFF] condition from the
accelerator position switch signal.
SPILL/V [ÉCA] qI
The control position of spill valve (sent
from electronic control fuel injection
pump) is displayed.
BATTERY VOLT [V] qqI
The power supply voltage of ECM is dis-
played.
P/N POSI SW
[ON/OFF] qqI
Indicates [ON/OFF] condition from the
park/neutral position switch signal.
START SIGNAL
[ON/OFF] qqI
Indicates [ON/OFF] condition from the
starter signal. I
After starting the engine, [OFF] is dis-
played regardless of the starter signal.
AIR COND SIG
[ON/OFF] qqI
Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
BRAKE SW [ON/OFF] qqI
Indicates [ON/OFF] condition from the
stop lamp switch signal.
IGN SW
[ON/OFF] qqI
Indicates [ON/OFF] condition from igni-
tion switch signal.
WARM UP SW
[ON/OFF] qI
Indicates [ON/OFF] condition from the
heat up switch signal.
MAS AIR/FL SE [V] qqI
The signal voltage of the mass air flow
sensor is displayed. I
When the engine is stopped, a certain
value is indicated.
DECELER F/CUT
[ON/OFF] qI
The [ON/OFF] condition from decelera-
tion fuel cut signal (sent from electronic
control fuel injection pump) is displayed.
INJ TIMG C/V [%] qI
The duty ratio of fuel injection timing
control valve (sent from electronic control
fuel injection pump) is displayed.
AIR COND RLY
[ON/OFF] qI
Indicates the control condition of the air
conditioner relay (determined by ECM
according to the input signals).
GLOW RLY [ON/OFF] qI
The glow relay control condition (deter-
mined by ECM according to the input
signal) is displayed.
COOLING FAN
[ON/OFF] qI
Indicates the control condition of the
cooling fans (determined by ECM
according to the input signal).
I ON ... Operates.
OFF ... Stopped.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
CONSULT-II (Cont'd)
EC-41
http://vnx.su/  
![NISSAN TERRANO 2004  Service Repair Manual Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
EGR VOL CON/V
[step] qI
Indicates the EGR volume control value
computed by the ECM according to the
input signals.
I The opening NISSAN TERRANO 2004  Service Repair Manual Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
EGR VOL CON/V
[step] qI
Indicates the EGR volume control value
computed by the ECM according to the
input signals.
I The opening](/manual-img/5/57394/w960_57394-316.png)
Monitored item
[Unit]ECM
input
signals Main
signals Description Remarks
EGR VOL CON/V
[step] qI
Indicates the EGR volume control value
computed by the ECM according to the
input signals.
I The opening becomes larger as the
value increases.
VNT S/V 1 [%] IIndicates the variable nozzle turbo-
charger control solenoid valve control
value computed by the ECM according
to the input signals.
BARO SEN [kPa]
qI
The barometric pressure (determined by
the signal voltage from the barometric
pressure sensor built into the ECM) is
displayed.
SWRL CON S/V 1
[ON/OFF]
qI
The control condition of the swirl control
valve control solenoid valve (determined
by ECM according to the input signals) is
indicated.
I ON ... Swirl control valve is closed.
I OFF ... Swirl control valve is opened.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
CONSULT-II (Cont'd)
EC-42
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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):
IThe 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, ªMONITORº
in ªDATA MONITORº screen is changed to ªRecording Data ...
xx%º as shown at left, and the data after the malfunction detec-
tion 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):
I 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
I While trying to detect the DTC by performing the ªDTC Confir-
mation Procedureº, be sure to select to ªDATA MONITOR
(AUTO TRIG)º mode. You can confirm the malfunction at the
moment it is detected.
I While narrowing down the possible causes, CONSULT-II
should be set in ªDATA MONITOR (AUTO TRIG)º mode, espe-
cially in case the incident is intermittent.
When you are inspecting the circuit by gently shaking (or twist-
ing) the suspicious connectors, components and harness 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 DIAG-
NOSIS FOR AN ELECTRICAL INCIDENTº.)
2) ªMANU TRIGº
I If the malfunction is displayed as soon as ªDATA MONITORº is
selected, reset CONSULT-II to ªMANU TRIGº. By selecting
ªMANU TRIGº you can monitor and store the data. The data
can be utilized for further diagnosis, such as a comparison with
the value for the normal operating condition.
SEF373Y
SEF707X
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
CONSULT-II (Cont'd)
EC-44
http://vnx.su/