
***: Not applicable
NEW TERMNEW ACRONYM/
ABBREVIATION OLD TERM
Exhaust gas recirculation temperature sensor EGR temperature sensor Exhaust gas temperature sensor
Flash electrically erasable programmable read
only memory FEEPROM ***
Flash erasable programmable read only memory FEPROM ***
Flexible fuel sensor FFS ***
Flexible fuel system FF system ***
Heated Oxygen sensor HO
2S Exhaust gas sensor
Idle air control system IAC systemIdle speed control
Idle air control valve-air regulator IACV-air regulatorAir regulator
Idle air control valve-auxiliary air control valve IACV-AAC valve Auxiliary air control (AAC) valve
Idle air control valve-FICD solenoid valve IACV-FICD solenoid valve FICD solenoid valve
Idle air control valve-idle up control solenoid
valve IACV-idle up control solenoid
valve
Idle up control solenoid valve
Idle speed control-FI pot ISC-FI potFI pot
Idle speed control system ISC system***
Ignition control module ICM***
Indirect fuel injection system IFI system***
Intake air temperature sensor IATS Air temperature sensor
Knock *** Detonation
Knock sensor KS Detonation sensor
Malfunction indicator MI Check engine light
Manifold absolute pressure MAP ***
Manifold absolute pressure sensor MAPS ***
Manifold differential pressure MDP ***
Manifold differential pressure sensor MDPS ***
Manifold surface temperature MST ***
Manifold surface temperature sensor MSTS ***
Manifold vacuum zone MVZ ***
Manifold vacuum zone sensor MVZS ***
Mass air flow sensor MAFS Air flow meter
Mixture control solenoid valve MC solenoid valve Air-fuel control solenoid valve
Multiport fuel injection system MFI system Fuel injection control
Neutral position switch *** Neutral switch
Non-volatile random access memory NVRAM ***
On-board diagnostic system OBD system Self-diagnosis
Open loop OL Open loop
Oxidation catalyst OC Catalyst
Oxidation catalytic converter system OC system ***
Oxygen sensor O
2S Exhaust gas sensor
Park position switch ***Park switch
Park/neutral position switch PNP switch Park/neutral switch
Periodic trap oxidizer system PTOX system ***
ISO 15031-2 TERMINOLOGY LIST
ISO 15031-2 Terminology List (Cont'd)
GI-35
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1. Warm up engine.
2. Turn ignition switch OFF.
3. Using CONSULT-II, make sure no error codes are indicated forself-diagnosis items. Refer to EC section, ªFuel Pressure
Releaseº.
I Do not disconnect CONSULT-II until the end of this operation;
it will be used to check engine rpm and for error detection at
the end of this operation.
4. Disconnect the negative battery terminal.
5. Remove the following parts.
I Intercooler
I Throttle body
I Rocker cover
6. To prevent fuel from being injected during inspection, remove fuel injection pump fuse [ENG CONT A/T (15A)] from fuse box
on the right side of engine compartment.
7. Remove glow plugs from all the cylinders.
I Before removal, clean the surrounding area to prevent
entry of any foreign materials into the engine.
I Carefully remove glow plugs to prevent any damage or
breakage.
I Handle with care to avoid applying any shock to glow
plugs.
8. Install adapter (SST) to installation holes of glow plugs and connect compression gauge for diesel engine.
:15-19N ×m (1.5 - 2.0 kg-m, 11 - 14 ft-lb)
9. Connect battery negative terminal.
10. Set the ignition switch to ªSTARTº and crank. When gauge pointer stabilizes, read compression pressure and engine rpm.
Repeat the above steps for each cylinder.
I Always use a fully-charged battery to obtain specified
engine speed.
Unit: kPa (bar, kg/cm2, psi)/rpm
Standard MinimumDifference limit between
cylinders
2,942 (29.42, 30.0, 427)/ 200 2,452 (24.52, 25.0, 356)/
200 294 (2.94, 3.0, 43)/200
I
When engine rpm is out of the specified range, check the spe-
cific gravity of battery liquid. Measure again under corrected
conditions.
I If engine rpm exceeds the limit, check valve clearance and
combustion chamber components (valves, valve seats, cylinder
head gaskets, piston rings, pistons, cylinder bores, cylinder
block upper and lower surfaces) and measure again.
11. Complete this operation as follows:
a. Turn the ignition switch to ªOFFº.
b. Disconnect battery negative terminal.
c. Replace glow plug oil seals and install glow plugs.
d. Install fuel injection pump fuse [ENG CONT A/T (15A)].
e. Connect battery negative terminal.
f. Using CONSULT-II make sure no error code is indicated for items of self-diagnosis. Refer to EC section, ªTrouble Diagno-
sis Ð Indexº.
YEM039
SEM334G
MEASUREMENT OF COMPRESSION PRESSUREZD
EM-10
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Measurement of Compression Pressure
1. Warm up engine and switch off the ignition switch.
2. Remove glow plate and glow plugs.
3. Fit compression gauge adapter to cylinder head.Compression gauge adapter:
:15-20N ×m
(1.5 - 2.0 kg-m, 11 - 14 ft-lb)
4. Ensure the ignition switch is in the ªLOCKº position and discon- nect harness connector (gray colored) from injection pump.
5. Crank engine, then read gauge indication.
I Always use a fully-charged battery to obtain specified
engine revolution.
I Engine compression measurement should be made as
quickly as possible.
Compression pressure:
Unit: kPa (bar, kg/cm2, psi)/200 rpm
Standard 2,942 (29.4, 30, 427)
Minimum 2,452 (24.5, 25, 356)
Differential limit between cylinders 294 (2.9, 3, 43)
6. If cylinder compression in one or more cylinders is low, pour a small amount of engine oil into cylinders through the glow holes
and retest compression.
I If adding oil helps the compression pressure, piston rings
may be worn or damaged.
I If pressure stays low, valve may be sticking or seating
incorrectly.
I If cylinder compression in any two adjacent cylinders is
low, and if adding oil does not help the compression, there
is leakage past the gasket surface.
Leakage past the cylinder gasket can result in oil and water
becoming mixed in the engine block cooling and lubrica-
tion chambers.
SEM618B
NEM005
SEM355F
COMPRESSION PRESSURETD27Ti
EM-103
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Precautions
IAlways use a 12 volt battery as power source.
I Do not attempt to disconnect battery cable while engine is
running.
I Before connecting or disconnecting the ECM harness
connector, turn ignition switch OFF and disconnect nega-
tive battery terminal. Failure to do so may damage the ECM
because battery voltage is applied to ECM even if ignition
switch is turned off.
I Before removing parts, turn off ignition switch and then
disconnect battery ground cable.
I Do not disassemble ECM.
I If a battery terminal is disconnected, the memory will
return to the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is
disconnected. However, this is not an indication of a prob-
lem. Do not replace parts because of a slight variation.
I When ECM is removed for inspection, make sure to ground
the ECM mainframe.
I When connecting ECM harness connector, tighten secur-
ing bolt until the gap between the orange indicators disap-
pears.
: 3.0 - 5.0 N ×m (0.3 - 0.5 kg-m, 26 - 43 in-lb)
I When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.
I Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in the circuit, thus resulting in damage
to ICs.
I Keep ECM harness at least 10 cm (3.9 in) away from adja-
cent harnesses, to prevent an ECM system malfunction
SEF706Y
SEC220B
SEF665S
SEF308Q
SEF291H
PRECAUTIONSZD30DDTi
EC-9
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System Chart
Input (Sensor)ECM FunctionOutput (Actuator)
I Electronic control fuel injection pump
I Crankshaft position sensor (TDC)
I Engine coolant temperature sensor
I Accelerator position sensor
I Accelerator position switch
I Accelerator switch (F/C)
I Park/Neutral position (PNP) switch
I Ignition switch
I Battery voltage
I Vehicle speed sensor
I Air conditioner switch
I Mass air flow sensor
I Stop lamp switch
I Heat up switch
I Charge air pressure sensor*1 Fuel injection control
Electronic control fuel injection pump
Fuel injection timing control Electronic control fuel injection pump
Fuel cut control Electronic control fuel injection pump
Glow control system Glow relay & glow lamp
On board diagnostic system MI (On the instrument panel)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Air conditioning cut control Air conditioner relay
Variable nozzle turbocharger control Variable nozzle turbocharger control sole- noid valve
Swirl control valve control Swirl control valve control solenoid valve
Intake air control valve control Intake air control valve control solenoid
valve
*1: This sensor is not used to control the engine system under normal conditions.
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
EC-19
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Fuel Injection Control System
DESCRIPTION
System description
Three types of fuel injection control are provided to accommodate engine operating conditions; normal control,
idle control and start control. The ECM determines the appropriate fuel injection control. Under each control,
the amount of fuel injected is compensated to improve engine performance.
Pulse signals are exchanged between ECM and electronic control fuel injection pump (control unit is built-in).
The fuel injection pump control unit performs duty control on the spill valve (built into the fuel injection pump)
according to the input signals to compensate the amount of fuel injected to the preset value.
Start control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection con-
trol (start control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC)
Engine speed
Ignition switch Start signal
When the ECM receives a start signal from the ignition switch, the
ECM adapts the fuel injection system for the start control. The
amount of fuel injected at engine starting is a preset program value
in the ECM. The program is determined by the engine speed and
engine coolant temperature.
For better startability under cool engine conditions, the lower the
coolant temperature becomes, the greater the amount of fuel
injected. The ECM ends the start control when the engine speed
reaches the specific value, and shifts the control to the normal or
idle control.
Idle control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection con-
trol (Idle control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC)
Engine speed
Park/Neutral position (PNP) switch Gear position
Battery Battery voltage
Accelerator position switch Idle position
Vehicle speed sensor Vehicle speed
Air conditioner switch Air conditioner signal
Heat up switch Heat up switch signal
When the ECM determines that the engine speed is at idle, the fuel injection system is adapted for the idle
control. The ECM regulates the amount of fuel injected corresponding to changes in load applied to the engine
to keep engine speed constant. The ECM also provides the system with a fast idle control in response to the
engine coolant temperature and heat up switch signal.
SEF648S
ENGINE AND EMISSION BASIC CONTROL SYSTEM
DESCRIPTIONZD30DDTi
EC-20
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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
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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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