
Diagnostic test mode I Ð Bulb check
In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to EL
section, ªWARNING LAMPS AND CHIMEº or see EC-291.
Diagnostic test mode I Ð Malfunction warning
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
Diagnostic test mode II Ð Self-diagnostic results
In this mode, DTC is indicated by the number of blinks of the MI as shown below.
Long (0.6 second) blinking indicates the two LH digits of number and short (0.3 second) blinking indicates the
two RH digits of number. For example, the MI blinks 10 times for 6 seconds (0.6 sec x 10 times) and then it
blinks three times for about 1 second (0.3 sec x 3 times). This indicates the DTC ª1003º.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC ª0505º refers to no
malfunction. (See TROUBLE DIAGNOSIS Ð INDEX, EC-7.)
How to erase diagnostic test mode II (Self-diagnostic results)
The DTC can be erased from the backup memory in the ECM when the diagnostic test mode is changed from
Diagnostic Test Mode II to Diagnostic Test Mode I. (Refer to ªHow to Switch Diagnostic Test Modesº, EC-36.)
IIf the battery terminal is disconnected, the DTC will be lost from the backup memory within 24
hours.
IBe careful not to erase the stored memory before starting trouble diagnoses.
SEF298QA
SEF162PB
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONZD30DDTi
Malfunction Indicator (MI) (Cont'd)
EC-37

ECM Terminals and Reference Value
PREPARATION
1. ECM is located behind the instrument lower panel. For this
inspection, remove the driver's side instrument lower cover.
2. Remove ECM harness protector.
3. Perform all voltage measurements with the connector con-
nected. Extend tester probe as shown to perform tests easily.
IOpen harness securing clip to make testing easier.
IUse extreme care not to touch 2 pins at one time.
IData is for comparison and may not be exact.
Be sure ECM unit is properly grounded before checking.
MEC020E
AEC913
SEF367I
SEF665S
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
EC-69

Component Description
The heat up switch is located on the lower side of the instrument
panel. This switch is used to speed up the heater's operation when
the engine is cold.
When the ECM received the heat up switch ªONº signal, the ECM
increases the engine idle speed to 1,100 to 1,200 rpm to warm up
engine quickly.
This system works when all conditions listed below are met.
Heat up switch ON
Engine coolant temperature Below 105ÉC (221ÉF)
Shift lever ªPº or ªNº
Accelerator pedal Fully released
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
WARM UP SWIIgnition switch: ONHeat up switch: ON ON
Heat up switch: OFF 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 CONDITIOND ATA
(DC Voltage and Pulse
Signal)
59 G Heat up switchIgnition switch ªONº
Heat up switch is ªOFFº.0V
Ignition switch ªONº
Heat up switch is ªONº.BATTERY VOLTAGE
(11 - 14V)
HEAT UP SWITCHZD30DDTi
EC-258

System Chart
Crankshaft position sensor
(TDC)E
ECM
Control sleeve position sensorE
Fuel temperature sensorE
Mass air flow sensorE
Engine coolant temperature sen-
sorE
Needle lift sensorE
Accelerator position sensorE
Accelerator position switchE
Air conditioner switchE
Ignition switchE
Battery voltageE
Vehicle speed sensorE
Brake switchE
Atmospheric pressure sensor
(inside ECM)E
EFuel injection controlEElectric governor
EFuel injection timing controlEInjection timing control valve
EFuel cut controlEFuel cut solenoid valve
EGlow control systemEGlow relay & glow lamp
EOn board diagnostic systemEMalfunction indicator lamp
(On the instrument panel)
EEGR valve & Throttle control
valve controlEEGRC-solenoid valve A, B and
throttle control solenoid valve
(models for Germany)
EAir conditioning cut controlEAir conditioner relay
ENGINE AND EMISSION CONTROL OVERALL SYSTEMTD27Ti
EC-305

DIAGNOSTIC TEST MODE IÐBULB CHECK
In this mode, the MALFUNCTION INDICATOR on the instrument panel should stay ON. If it remains OFF,
check the bulb. Refer to EL section (ªWARNING LAMPS/WIRING DIAGRAMº) or see EC-452.
DIAGNOSTIC TEST MODE IÐMALFUNCTION WARNING
MI Condition
ON When a malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
IThese Diagnostic Trouble Code Numbers are clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC
RESULTS).
DIAGNOSTIC TEST MODE IIÐSELF-DIAGNOSTIC RESULTS
In this mode, DTC is indicated by the number of blinks of the MI as shown below.
Long (0.6 second) blinking indicates the two LH digits of number and short (0.3 second) blinking indicates the
two RH digits of number. For example, the MI blinks 10 times for 6 seconds (0.6 sec x 10 times) and then it
blinks three times for about 1 second (0.3 sec x 3 times). This indicates the DTC ª1003º.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC ª0505º refers to no
malfunction. (See TROUBLE DIAGNOSIS Ð INDEX, EC-293.)
HOW TO ERASE DIAGNOSTIC TEST MODE II (Self-diagnostic results)
The diagnostic trouble code can be erased from the backup memory in the ECM when the diagnostic test mode
is changed from Diagnostic Test Mode II to Diagnostic Test Mode I repeating consecutively twice. (Refer to
ªHOW TO SWITCH DIAGNOSTIC TEST MODESº on previous page.)
IIf the battery terminal is disconnected, the diagnostic trouble code will be lost from the backup
memory within 24 hours.
IBe careful not to erase the stored memory before starting trouble diagnoses.
IIf the MI flashes or ªNATS MALFUNCTIONº is displayed on ªSELF-DIAG RESULTSº screen, perform
self-diagnostic results mode with CONSULT-II using NATS program card (NATS-E940). Refer to 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, initialisation of NATS system and registration of all NATS ignition key IDs
must be carried out with CONSULT-II using NATS program card (NATS-E940).
Therefore, be sure to receive all keys from vehicle owner.
SEF298QA
SEF162PB
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONTD27Ti
Malfunction Indicator (MI) (Cont'd)
EC-324

Component Description
Malfunction Indicator (MI) is located on the instrument panel. When the ignition switch is turned ON without
engine running, MI will light up. This is a bulb check. When the engine is started, MI should go off. If MI remains
on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnosis Logic
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0650
0907Malfunction indicator (MI) control cir-
cuitIAn excessively high voltage is sent
to ECM through the MI circuit
under the condition that calls for MI
light up.
IAn excessively low voltage is sent
to ECM through the MI circuit
under the condition that calls for MI
not to light up.IHarness or connectors
(MI circuit is open or shorted.)
IMI
DTC Confirmation Procedure
NOTE:
If ªDTC Confirmation Procedureº has been previously
conducted, always turn ignition switch ªOFFº and wait at least
10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªDATA MONITORº mode with CONSULT-II.
3. Start engine and let it idle for 2 second.
WITHOUT CONSULT-II
1. Turn ignition switch ªONº.
2. Perform ªDiagnostic Test Mode IIº (Self-diagnostic results).
3. Start engine and let it idle for 2 second.
4. Perform ªDiagnostic Test Mode IIº (Self-diagnostic results).
SEF817Y
DTC P0650 MITD27Ti
EC-404

insulation (either just before the harness connectors or for
the complete harness), for easy identification.
Precautions for NATS
NATS (Nissan Anti-Theft System)
NATS will immobilize the engine if someone tries to start it without
the registered key of NATS.
Both of the originally supplied ignition key IDs have been NATS
registered.
The NATS security indicator is located on the instrument panel. The
indicator blinks when the ignition switch is in ªOFFº or ªACCº posi-
tion. Therefore, NATS warns outsiders that the vehicle is equipped
with the anti-theft system.
IWhen NATS detects trouble, the malfunction indicator lamp
(MIL) blinks.
This blinking indicates that the anti-theft is not functioning, so
prompt service is required.
IIf the malfunction indicator lamp comes on while the engine is
running, return the vehicle to the workshop before turning the
ignition switch ªOFFº.
Once the ignition switch is turned ªOFFº, the engine can not be
started.
IWhen servicing NATS (trouble diagnoses, system initialization
and additional registration of other NATS ignition key IDs) CON-
SULT-II hardware and CONSULT-II NATS software is neces-
sary.
Regarding the procedures of NATS initialization and NATS igni-
tion key ID registration, refer to CONSULT-II operation manual,
NATS.
Therefore, CONSULT-II NATS software (program card and
operation manual) must be kept strictly confidential to main-
tain the integrity of the anti-theft function.
IWhen servicing NATS (trouble diagnoses, system initialization
and additional registration of other NATS ignition key IDs), it
may be necessary to re-register original key identification.
Therefore, be sure to receive all keys from vehicle owner.
A maximum of five key IDs can be registered into NATS.
IWhen failing to start the engine first-time using the key of
NATS, starts as follows:
(1) Turn ignition key to ªOFFº.
(2) Wait approx. 5 seconds.
(3) Turn ignition key to ªSTARTº again while keeping the key
apart from any others on key-chain.
SGI916
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
(Dual Air Bag System) (Cont'd)
GI-4

Engine compartment
There are several reasons a vehicle or engine vibration could
cause an electrical complaint. Some of the things to check for are:
IConnectors not fully seated.
IWiring harness not long enough and is being stressed due to
engine vibrations or rocking.
IWires laying across brackets or moving components.
ILoose, dirty or corroded ground wires.
IWires routed too close to hot components.
To inspect components under the hood, start by verifying the integ-
rity of ground connections. (Refer to GROUND INSPECTION
described later.) First check that the system is properly grounded.
Then check for loose connection bygently shakingthe wiring or
components as previously explained. Using the wiring diagrams
inspect the wiring for continuity.
Behind the instrument panel
An improperly routed or improperly clamped harness can become
pinched during accessory installation. Vehicle vibration can aggra-
vate a harness which is routed along a bracket or near a screw.
Under seating areas
An unclamped or loose harness can cause wiring to be pinched by
seat components (such as slide guides) during vehicle vibration. If
the wiring runs under seating areas, inspect wire routing for pos-
sible damage or pinching.
HEAT SENSITIVE
The owner's problem may occur during hot weather or after car has
sat for a short time. In such cases you will want to check for a heat
sensitive condition.
To determine if an electrical component is heat sensitive, heat the
component with a heat gun or equivalent.
Do not heat components above 60ÉC (140ÉF).If incident occurs
while heating the unit, either replace or properly insulate the com-
ponent.
SGI842
HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont'd)
GI-24