Page 373 of 1767

IDo not disconnect pump harness connector with engine
running.
IDo not disassemble electronic fuel injection pump.
If NG, take proper action.
IDo not disassemble injection nozzle.
If NG, replace injection nozzle.
IEven a slight leak in the air intake system can cause seri-
ous problems.
IDo not shock or jar the crankshaft position sensor (TDC).
IDo not depress accelerator pedal when starting.
IImmediately after starting, do not rev up engine unneces-
sarily.
IDo not rev up engine just prior to shutdown.
IWhen installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on its installation loca-
tion.
1) Keep the antenna as far as possible away from the ECM.
2) Keep the antenna feeder line more than 20 cm (7.9 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
3) Adjust the antenna and feeder line so that the standing-
wave ratio can be kept smaller.
4) Be sure to ground the radio to vehicle body.
SEF437Y
SEF709Y
SEF708Y
PRECAUTIONSZD30DDTi
Precautions (Cont'd)
EC-11
Page 395 of 1767

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.
IOutput 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
Page 396 of 1767

IIf the battery is disconnected, the emission-related diagnostic information will be lost after approx.
24 hours.
IErasing 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.
IConfirm no self-diagnostic results of NATS is displayed
before touching ªERASEº in ªSELF-DIAG RESULTSº mode
with CONSULT-II.
IWhen 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.
IIf the MI does not light up, refer to EL section (ªWARNING
LAMPS AND CHIMEº) or see EC-291.
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
Page 397 of 1767
On board diagnostic system function
The on board diagnostic system has the following three functions.
Diagnostic Test Mode KEY and ENG. Status Function Explanation 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-291.)
Engine running
MALFUNCTION
WARNINGThis 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
Page 400 of 1767
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
Page 428 of 1767

CONSULT-II Reference Value in Data Monitor
Mode
Remarks:
ISpecification data are reference values.
ISpecification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
MONITOR ITEM CONDITION SPECIFICATION
CKPS×RPM (TDC)
ITachometer: Connect
IRun engine and compare tachometer indication with the CONSULT-II value.Almost the same speed as the
CONSULT-II value.
CMPS×RPM-PUMP
COOLAN TEMP/SIEngine: After warming up More than 70ÉC (158ÉF)
VHCL SPEED SEITurn drive wheels and compare speedometer indication with the CONSULT-II valueAlmost the same speed as the
CONSULT-II value
FUEL TEMP SENIEngine: After warming up More than 40ÉC (104ÉF)
ACCEL POS SENIIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released 0.40 - 0.60V
Accelerator pedal: fully depressed Approx. 4.5V
FULL ACCEL SWIIgnition switch: ON
(Engine stopped)Accelerator pedal: fully depressed ON
Except above OFF
ACCEL SW (FC)IIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released CLOSE
Accelerator pedal: slightly open OPEN
OFF ACCEL SWIIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released ON
Accelerator pedal: slightly open OFF
SPILL/VIEngine: After warming up Approx. 13ÉCA
BATTERY VOLTIIgnition switch: ON (Engine stopped) 11 - 14V
P/N POSI SWIIgnition switch: ONShift lever: Park/Neutral ON
Except above OFF
START SIGNALIIgnition switch: ON,START,ON OFF,ON,OFF
AIR COND SIGIEngine: After warming up, idle the
engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
BRAKE SWIIgnition switch: ONBrake pedal: depressed ON
Brake pedal: released OFF
IGN SWIIgnition switch: ON,OFF ON,OFF
WARM UP SWIIgnition switch: ONHeat up switch: ON ON
Heat up switch: OFF OFF
MAS AIR/FL SEIEngine: After warming up
IAir conditioner switch: OFF
IShift lever: Neutral position
INo-loadIdle 1.6 - 2.0V
DECELER F/CUTIEngine: After warming up Idle OFF
INJ TIMG C/VIEngine: After warming up, idle the engine. Approx. 50 - 70%
AIR COND RLYIEngine: After warming up, idle the
engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
GLOW RLYIRefer to EC-239.
COOLING FANIWhen cooling fan is stopped. OFF
IWhen cooling fan operates. ON
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
EC-66
Page 466 of 1767

Description
The accelerator switch is installed to the accelerator pedal assem-
bly. The switch senses accelerator position and sends an ON-OFF
signal to the ECM. The ECM uses the signal to control the fuel cut
operation at deceleration for better fuel efficiency.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SW (FC)IIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released CLOSE
Accelerator pedal: slightly open OPEN
DECELER F/CUTIEngine: After warming up Idle OFF
ECM Terminals and Reference Value
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
29 LG/R Accelerator switch (F/C)Ignition switch ªONº
Accelerator pedal fully releasedBATTERY VOLTAGE
(11 - 14V)
Ignition switch ªONº
Accelerator pedal depressedApproximately 0V
On Board Diagnosis Logic
Malfunction is detected when .... Check Items (Possible Cause)
IThe OFF signal (short) is sent to the ECM for a certain period
of time even when the accelerator pedal is not being
depressed.IHarness or connectors
(The switch circuit is shorted.)
IAccelerator switch (F/C)
MEC986D
DTC 0203 ACCEL POS SW (F/C)ZD30DDTi
EC-104
Page 492 of 1767

Description
The accelerator position sensor is installed on the upper end of the accelerator pedal assembly. The sensor
detects the accelerator position and sends a signal to the ECM. The ECM uses the signal to determine the
amount of fuel to be injected.
The accelerator position switch detects Off-accelerator switch signal and Full-accelerator switch signal and
send these signals to the ECM. The ECM will then determine engine idle conditions. These signals are also
used for diagnosing the accelerator position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
ACCEL POS SENIIgnition switch: ON
(Engine stopped)Accelerator pedal: released 0.40 - 0.60V
Accelerator pedal: depressed Approx. 4.5V
FULL ACCEL SWIIgnition switch: ON
(Engine stopped)Accelerator pedal: fully depressed ON
Except above OFF
OFF ACCEL SWIIgnition switch: ON
(Engine stopped)Accelerator pedal: fully released ON
Accelerator pedal: slightly open OFF
SEF861SA
DTC 0403 ACCEL POS SENSORZD30DDTi
EC-130