
Normal control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Crankshaft position sensor (TDC) Engine speed
Fuel injection con-
trol (Normal con-
trol)Electronic control fuel injec-
tion pump
Accelerator position sensor
Accelerator position
Vehicle speed sensor Vehicle speed
The amount of fuel injected under normal driving conditions is
determined according to sensor signals. The crankshaft position
sensor (TDC) detects engine speed and the accelerator position
sensor detects accelerator position. These sensors send signals to
the ECM.
The fuel injection data, predetermined by correlation between vari-
ous engine speeds and accelerator positions, are stored in the
ECM memory, forming a map. The ECM determines the optimal
amount of fuel to be injected using the sensor signals in compari-
son with the map.
Maximum amount control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Mass air flow sensor Amount of intake air
Fuel injection con-
trol (Maximum
amount control)Electronic control fuel injec-
tion pump
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (TDC) Engine speed
Accelerator position sensor Accelerator position
The maximum injection amount is controlled to an optimum by the engine speed, intake air amount, engine
coolant temperature, and accelerator opening in accordance with the driving conditions.
This prevents the oversupply of the injection amount caused by decreased air density at a high altitude or
during a system failure.
Deceleration control
Input/output signal chart
Sensor
Input Signal to ECM ECM Function Actuator
Accelerator switch (F/C) Accelerator positionFuel injection con-
trol (Deceleration
control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC) Engine speed
The ECM sends a fuel cut signal to the electronic control fuel injection pump during deceleration for better
fuel efficiency. The ECM determines the time of deceleration according to signals from the accelerator switch
(F/C) and crankshaft position sensor (TDC).
SEF649S
ENGINE AND EMISSION BASIC CONTROL SYSTEM
DESCRIPTIONZD30DDTi
Fuel Injection Control System (Cont'd)
EC-21
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Fuel Injection Timing Control System
DESCRIPTION
The target fuel injection timing in accordance with the engine speed and the fuel injection amount are recorded
as a map in the ECM beforehand. The ECM and the injection pump control unit exchange signals and per-
form feedback control for optimum injection timing in accordance with the map.
Air Conditioning Cut Control
DESCRIPTION
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Air conditioner switch Air conditioner ªONº signal
Air conditioner cut
controlAir conditioner relay
Accelerator position sensor
Accelerator valve opening
angle
Vehicle speed sensor Vehicle speed
Engine coolant temperature sensor Engine coolant temperature
System description
This system improves acceleration when the air conditioner is used.
When the accelerator pedal is fully depressed, the air conditioner is turned off for a few seconds.
When engine coolant temperature becomes excessively high, the air conditioner is turned off. This continues
until the engine coolant temperature returns to normal.
Fuel Cut Control (at no load & high engine
speed)
DESCRIPTION
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Vehicle speed sensor Vehicle speed
Fuel cut controlElectronic control fuel injec-
tion pump
Park/Neutral position (PNP) switch
Neutral position
Accelerator position switch or Accelerator
switch (F/C) Accelerator position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (TDC) Engine speed
If the engine speed is above 2,700 rpm with no load (for example, in neutral and engine speed over 2,700
rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies based on engine speed.
Fuel cut will operate until the engine speed reaches 1,500 rpm, then fuel cut is cancelled.
NOTE:
This function is different from deceleration control listed under ªFuel Injection Control Systemº, EC-20.
ENGINE AND EMISSION BASIC CONTROL SYSTEM
DESCRIPTIONZD30DDTi
EC-22
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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
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![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
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![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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ACTIVE TEST MODE
TEST ITEMCONDITION JUDGEMENTCHECK ITEM (REMEDY)
COOLING FAN I
Ignition switch: ON
I Operate the cooling fan at
ªLOWº, ªHIº speed and turn
ªOFFº using CONSULT-II. Cooling fan moves at ªLOWº, ªHIº
speed and stops.
I
Harness and connector
I Cooling fan motor
I Cooling fan relay
OFF ACCEL PO
SIG I
Clears the self-learning fully closed accelerator position, detected by accelerator position sensor, from the
ECM.
GLOW RLY I
Ignition switch: ON (Engine
stopped)
I Turn the glow relay ªONº and
ªOFFº using CONSULT-II and
listen to operating sound. Glow relay makes the operating
sound.
I
Harness and connector
I Glow relay
INJ TIMING* I
Engine: Return to the original
trouble condition
I Retard the injection timing using
CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.
I
Electronic control fuel injection
pump
SWIRL CONT S/V1 I
Ignition switch: ON
I Turn solenoid valve ªONº and
ªOFFº with the CONSULT-II and
listen to operating sound. Solenoid valve makes an operating
sound.
I
Harness and connector
I Solenoid valve
EGR VOL CONT/V I
Ignition switch: ON
I Change EGR volume control
valve opening step using CON-
SULT-II. EGR volume control valve makes
an operating sound.
I
Harness and connector
I EGR volume control valve
*: When using this item, DTC 0707 ªP7 ×F/INJ TIMG FBº may be detected. If so, erase it because it is not a malfunction.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
CONSULT-II (Cont'd)
EC-43
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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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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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