
ENGINE CONTROL SYSTEMSECTION
EC
CONTENTS
ZD30DDTi
TROUBLE DIAGNOSIS - INDEX ....................................7
Alphabetical & Numerical Index for DTC ....................7
PRECAUTIONS ...............................................................9
Precautions ..................................................................9
ENGINE AND EMISSION CONTROL OVERALL
SYSTEM ........................................................................\
.12
Engine Control Component Parts Location ...............12
Circuit Diagram ..........................................................16
System Diagram ........................................................17
Vacuum Hose Drawing ..............................................18
System Chart .............................................................19
ENGINE AND EMISSION BASIC CONTROL
SYSTEM DESCRIPTION ...............................................20
Fuel Injection Control System ...................................20
Fuel Injection Timing Control System........................22
Air Conditioning Cut Control ......................................22
Fuel Cut Control (at no load & high engine
speed) ........................................................................\
22
Crankcase Ventilation System ...................................23
BASIC SERVICE PROCEDURE ...................................24
Injection Tube and Injection Nozzle ..........................24
Electronic Control Fuel Injection Pump .....................27
Air Bleeding ...............................................................32
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION ...............................................................33
DTC and MI Detection Logic .....................................33
Diagnostic Trouble Code (DTC) ................................33
Malfunction Indicator (MI) ..........................................34
CONSULT-II ...............................................................39
TROUBLE DIAGNOSIS - INTRODUCTION ..................46
Introduction ................................................................46
Work Flow ..................................................................48
TROUBLE DIAGNOSIS - BASIC INSPECTION ...........50
Basic Inspection.........................................................50
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION ...............................................................56
Symptom Matrix Chart ...............................................56 CONSULT-II Reference Value in Data Monitor
Mode ........................................................................\
..66
Major Sensor Reference Graph in Data Monitor
Mode ........................................................................\
..68
ECM Terminals and Reference Value .......................69
TROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENT .......................................................................78
Description .................................................................78
Diagnostic Procedure ................................................78
TROUBLE DIAGNOSIS FOR POWER SUPPLY ..........79
Main Power Supply and Ground Circuit ....................79
DTC 0102 MASS AIR FLOW SEN ................................88
Component Description .............................................88
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................\
..88
ECM Terminals and Reference Value .......................88
On Board Diagnosis Logic.........................................88
DTC Confirmation Procedure ....................................89
Wiring Diagram ..........................................................90
Diagnostic Procedure ................................................92
DTC 0103 COOLANT TEMP SEN ................................95
Description .................................................................95
On Board Diagnosis Logic.........................................95
DTC Confirmation Procedure ....................................95
Wiring Diagram ..........................................................96
Diagnostic Procedure ................................................97
DTC 0104 VEHICLE SPEED SEN ................................99
Description .................................................................99
ECM Terminals and Reference Value .......................99
On Board Diagnosis Logic.........................................99
Overall Function Check ...........................................100
Wiring Diagram ........................................................101
Diagnostic Procedure ..............................................103
DTC 0203 ACCEL POS SW (F/C) ..............................104
Description ...............................................................104
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................\
104
ECM Terminals and Reference Value .....................104
On Board Diagnosis Logic.......................................104
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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
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Crankcase Ventilation System
DESCRIPTION
In this system, blow-by gas is sucked into the air inlet pipe after oil
separation by oil separator in the rocker cover.
INSPECTION
Ventilation hose
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If anyhose cannot be freed of obstructions, replace.
JEF224Z
SEC692
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONZD30DDTi
EC-23
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REMOVAL
1. Remove the following:
IEngine coolant draining
I Charge air cooler
I Air inlet pipe
I Throttle body
I Rocker cover
I Oil level gauge guide
I EGR cooler
I EGR guide tube
I EGR volume control solenoid valve
I Fuel hose
I Injection tube
I Radiator upper hose
I Radiator shroud
I Cooling fan
I Drive belt
I Vacuum pipe
I Vacuum pump
2. Move the power steering pump.
3. Remove the harness connector from the fuel injection pump.
I After pulling the connector stopper all the way back, remove the
connector.
I When the stopper is pulled all the way back, the interlocked-
connector will come off.
As for installation, when the connector is pushed all the way
forward until the stopper locks, the interlocked-connector is
inserted.
4. Remove the fuel injection pump rear bracket.
5. Remove the chain cover.
I Remove the installation bolts A, B, and C shown in the figure
(left).
CAUTION:
During chain cover removal, seal the opening to prevent for-
eign objects from getting into the engine.
6. Fix the internal mechanism of the idler gear (scissors gear structure).
a. Remove the plug on the front side of the gear case.
b. While turning the crankshaft pulley clockwise, check the tight- ening bolt hole of the idler gear internal mechanism through the
plug hole.
I Conduct the visual check using a mirror.
I When checking, note that there are 2 other holes (with no
thread) beside the tightening bolt hole on the idler gear.
JEF260Z
JEF261Z
JEF262Z
BASIC SERVICE PROCEDUREZD30DDTi
Electronic Control Fuel Injection Pump (Cont'd)
EC-28
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13. Make the mating marks on the fuel injection pump flange andfront plate with paint.
14. Remove installation bolts first, and then fuel injection pump toward the rear side of the engine.
I When the fuel injection pump is stationary, it can still be
retained by the dowel without all bolts.
CAUTION:
Do not disassemble or adjust the fuel injection pump.
INSTALLATION
I The injection timing adjustment to correct the installation angle
deviation is not necessary. Install the pump in the proper posi-
tion according to the dowel and installation bolts.
1. Install the fuel injection pump from the rear side of the engine.
I Match the dowel of the spacer to the dowel hole of the pump
side for installation.
I Replace the seal washer of the installation bolt with a new one.
2. Align the mating marks of the fuel injection pump flange and front plate, and then adjust the approximate flange position.
I Each hole [6 mm (0.24 in) dia.] is used as a reference point for
the fuel injection pump flange, fuel injection pump gear, and fuel
injection pump sprocket.
I Only during removal/installation at No. 1 cylinder compression
top dead center, can the hole [6 mm (0.24 in) dia.] of the pump
body be aligned.
3. Install the fuel injection pump sprocket and gear as an assem- bly.
I Align the mating marks of the idler gear and fuel injection pump
gear properly.
4. Tighten the installation bolt of the fuel injection pump sprocket.
I Fix the fuel injection pump gear with the pulley holder (SST),
and tighten the installation bolt.
CAUTION:
Before tightening the installation bolt, check again that the
mating marks of the idler gear and fuel injection pump gear are
aligned.
JEF268Z
JEF269Z
JEF270Z
JEF271Z
JEF267Z
BASIC SERVICE PROCEDUREZD30DDTi
Electronic Control Fuel Injection Pump (Cont'd)
EC-30
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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
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On board diagnostic system function
The on board diagnostic system has the following three functions.
Diagnostic Test Mode KEY and ENG. StatusFunctionExplanation of Function
Mode I Ignition switch in ON
position
Engine stopped
BULB CHECK This function checks the MI bulb for damage
(blown, open circuit, etc.).
If the MI does not come on, check MI circuit.
(See EC-310.)
Engine running
MALFUNCTION
WARNING This is a usual driving condition. When ECM
detects a malfunction, the MI will light up to
inform the driver that a malfunction has been
detected.
Mode II Ignition switch in ON position
Engine stopped
SELF-DIAGNOSTIC RESULTS This function allows DTCs to be read.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
Malfunction Indicator (MI) (Cont'd)
EC-35
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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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