
Items
(CONSULT-II screen terms)DTC*1 SRT codeTest value/Test
limit
(GST only)1st trip DTC*1 Reference page
SFT SOL A/CIRC P0750 Ð Ð XRefer to AT sec-
tion.
SFT SOL B/CIRC P0755 Ð Ð XRefer to AT sec-
tion.
INT/V TIM V/CIR-B1 P1111 Ð Ð XEC-393
SWIRL CONT SOL/V*3 P1131 Ð Ð X EC-399
ENG OVER TEMP P1217 Ð Ð X EC-406
EGR TEMP SEN/CIRC*3 P1401 Ð Ð X EC-418
EGR SYSTEM*3 P1402 X X X*2 EC-425
A/T DIAG COMM LINE P1605 Ð Ð X EC-434
TP SEN/CIRC A/T P1705 Ð Ð XRefer to AT sec-
tion.
P-N POS SW/CIRCUIT P1706 Ð Ð X EC-437
O/R CLTCH SOL/CIRC P1760 Ð Ð XRefer to AT sec-
tion.
*1: 1st trip DTC No. is the same as DTC No.
*2: These are not displayed with GST.
*3: If so equipped
How to Erase Emission-related Diagnostic InformationNJEC0031S0106How to Erase DTC (With CONSULT-II)
NOTE:
If the DTC is not for A/T related items (see EC-10), skip steps 2 through 4.
1) If the ignition switch stays ªONº after repair work, be sure to turn ignition switch ªOFFº once. Wait at least
9 seconds and then turn it ªONº (engine stopped) again.
2) Turn CONSULT-II ªONº and touch ªA/Tº.
3) Touch ªSELF-DIAG RESULTSº.
4) Touch ªERASEº. [The DTC in the TCM (Transmission control module) will be erased.] Then touch ªBACKº
twice.
5) Touch ªENGINEº.
6) Touch ªSELF-DIAG RESULTSº.
7) Touch ªERASEº. (The DTC in the ECM will be erased.)
+If DTCs are displayed for both ECM and TCM (Transmission control module), they need to be erased
individually from the ECM and TCM (Transmission control module).
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Emission-related Diagnostic Information (Cont'd)
EC-70

Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but
all of the data listed above, are cleared from the ECM memory during work procedures.
MODELS WITHOUT EURO-OBD SYSTEMNJEC0031S07DTC and 1st Trip DTCNJEC0031S0701The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. If the same mal-
function is not detected in the 2nd trip (meeting the required driving pattern), the 1st trip DTC is cleared from
the ECM memory. If the same malfunction is detected in the 2nd trip, both the 1st trip DTC and DTC are stored
in the ECM memory. In other words, the DTC is stored in the ECM memory when the same malfunction occurs
in two consecutive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the
1st and 2nd trips, only the 1st trip DTC will continue to be stored. For fail-safe items, the DTC is stored in the
ECM memory even in the 1st trip.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in ªHow to Erase
Emission-related Diagnostic Informationº, EC-73.
When a (1st trip) DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in ªWork Flowº procedure Step II, refer to EC-98. Then perform ªDTC Confirmation Proce-
dureº or ªOverall Function Checkº to try to duplicate the problem. If the malfunction is duplicated, the item
requires repair.
How to Read DTC and 1st Trip DTC
DTC and 1st trip 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: 0100, 0115, 0340, 1335, etc.
With CONSULT-II
CONSULT-II displays the DTC in ªSELF-DIAG RESULTSº mode. Examples: P0100, P0115, P0340, P1335,
etc.
(CONSULT-II also displays the malfunctioning component or system.)
+1st trip DTC No. is the same as DTC No.
+Output of a DTC indicates a malfunction. However, ECM in the diagnostic test mode II (Self-diag-
nostic results) (If so equipped) does not indicate whether the malfunction is still occurring or has
occurred in the past and has returned to normal. CONSULT-II can identify malfunction status as
shown below. Therefore, the use of CONSULT-II (if available) is recommended.
A sample CONSULT-II display for DTC and 1st trip DTC is shown below. DTC or 1st trip DTC of a malfunc-
tion is displayed in the SELF-DIAGNOSTIC RESULTS mode of CONSULT-II. Time data indicates how many
times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be ª0º.
If a 1st trip DTC is stored in the ECM, the time data will be ª[1t]º.
SEF992X
Freeze Frame Data and 1st Trip Freeze Frame DataNJEC0031S0702The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant
temperature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, throttle valve opening, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II. For
details, see EC-86.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Emission-related Diagnostic Information (Cont'd)
EC-72

SEF543X
NATS (Nissan Anti-theft System)NJEC0591+If the security indicator lights up with the ignition switch
in the ªONº position or ªNATS MALFUNCTIONº is dis-
played on ªSELF-DIAG RESULTSº screen, perform self-
diagnostic results mode with CONSULT-II using NATS pro-
gram card. Refer to NATS (Nissan Anti-Theft System) in EL
section.
+Confirm no self-diagnostic results of NATS is displayed
before touching ªERASEº in ªSELF-DIAG RESULTSº
mode with CONSULT-II.
+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 procedure of NATS initialization and NATS
ignition key ID registration, refer to CONSULT-II operation
manual, NATS.
Malfunction Indicator (MI)
DESCRIPTIONNJEC0032
SAT652J
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without the engine running. This is a bulb check.
+If the MI does not light up, refer to EL-184, ªWARNING LAMPSº or see EC-591.
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.
On Board Diagnostic System FunctionNJEC0032S01The on board diagnostic system has the following four functions.
Diagnostic Test Mode I
1. BULB CHECK:
This function checks the MI bulb for damage (blown, open circuit, etc.).
If the MI does not come on, check MI circuit and ECM test mode selector. (See the following page.)
2. MALFUNCTION WARNING:
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
NATS (Nissan Anti-theft System)
EC-74

Diagnostic Test Mode I Ð Bulb CheckNJEC0032S03In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the MI bulb. Refer to
EL-184, ªWARNING LAMPSº or see EC-591.
Diagnostic Test Mode I Ð Malfunction WarningNJEC0032S04
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
+These DTC numbers are clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS).
Diagnostic Test Mode II Ð Self-diagnostic Results (If so equipped)NJEC0032S05In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MI as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MI does not illuminate in diagnostic test mode
I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MI illu-
minates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are
displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These uni-
dentified codes can be identified by using the CONSULT-II or GST. A DTC will be used as an example for how
to read a code.
SEF952W
A particular trouble code can be identified by the number of four-digit numeral flashes. The ªzeroº is indicated
by the number of ten flashes. The length of time the 1000th-digit numeral flashes on and off is 1.2 seconds
consisting of an ON (0.6-second)-OFF (0.6-second) cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0 second OFF. In other words, the lat-
ter numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8 second off.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC ª0000º refers to no
malfunction. (See TROUBLE DIAGNOSIS Ð INDEX, EC-10.)
How to Erase Diagnostic Test Mode II (Self-diagnostic results)
NJEC0032S0501The 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-76.)
+If the battery is disconnected, the DTC will be lost from the backup memory after approx. 24 hours.
+Be careful not to erase the stored memory before starting trouble diagnoses.
Diagnostic Test Mode II Ð Heated Oxygen Sensor 1 Monitor (Front) (If so equipped)NJEC0032S06In this mode, the MI displays the condition of the fuel mixture (lean or rich) which is monitored by the heated
oxygen sensor 1 (front).
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Malfunction Indicator (MI) (Cont'd)
EC-77

MI Fuel mixture condition in the exhaust gas Air fuel ratio feedback control condition
ON Lean
Closed loop system
OFF Rich
*Remains ON or OFF Any condition Open loop system
*: Maintains conditions just before switching to open loop.
To check the heated oxygen sensor 1 (front) function, start engine in the Diagnostic Test Mode II and warm
it up until engine coolant temperature indicator points to the middle of the gauge.
Next run engine at about 2,000 rpm for about 2 minutes under no-load conditions. Then make sure that the
MI comes ON more than 5 times within 10 seconds with engine running at 2,000 rpm under no-load.
OBD System Operation Chart (With Euro-OBD
Models Only)
NJEC0033RELATIONSHIP BETWEEN MI, 1ST TRIP DTC, DTC, AND DETECTABLE ITEMSNJEC0033S01+When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are
stored in the ECM memory.
+When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MI will come on. For details, refer to ªTwo Trip Detection Logicº on
EC-59.
+The MI will go off after the vehicle is driven 3 times with no malfunction. The drive is counted only when
the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs while counting,
the counter will reset.
+The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A)
without the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel
Injection System, the DTC and freeze frame data will be stored until the vehicle is driven 80 times (driv-
ing pattern C) without the same malfunction recurring. The ªTIMEº in ªSELF-DIAGNOSTIC RESULTSº
mode of CONSULT-II will count the number of times the vehicle is driven.
+The 1st trip DTC is not displayed when the self-diagnosis results in ªOKº for the 2nd trip.
SUMMARY CHARTNJEC0033S02
Items Fuel Injection System Misfire Other
MI (goes off) 3 (pattern B) 3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no display) 80 (pattern C) 80 (pattern C) 40 (pattern A)
1st Trip DTC (clear) 1 (pattern C), *1 1 (pattern C), *1 1 (pattern B)
1st Trip Freeze Frame Data (clear) *1, *2 *1, *2 1 (pattern B)
For details about patterns ªBº and ªCº under ªFuel Injection Systemº and ªMisfireº, see EC-80.
For details about patterns ªAº and ªBº under ªOtherº, see EC-82.
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Malfunction Indicator (MI) (Cont'd)
EC-78

RELATIONSHIP BETWEEN MI, DTC, 1ST TRIP DTC AND DRIVING PATTERNS FOR
ªMISFIREº
NJEC0033S03
SEF392SA
*1: When the same malfunction is
detected in two consecutive trips,
MI will light up.
*2: MI will go off after vehicle is driven
3 times (pattern B) without any
malfunctions.
*3: When the same malfunction is
detected in two consecutive trips,
the DTC and the freeze frame
data will be stored in ECM.
*4: The DTC and the freeze framedata will not be displayed any
longer after vehicle is driven 80
times (pattern C) without the same
malfunction.
(The DTC and the freeze frame
data still remain in ECM.)
*5: When a malfunction is detected
for the first time, the 1st trip DTC
and the 1st trip freeze frame data
will be stored in ECM.
*6: The 1st trip DTC and the 1st tripfreeze frame data will be cleared
at the moment OK is detected.
*7: When the same malfunction is
detected in the 2nd trip, the 1st
trip freeze frame data will be
cleared.
*8: 1st trip DTC will be cleared when
vehicle is driven once (pattern C)
without the same malfunction after
DTC is stored in ECM.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
OBD System Operation Chart (With Euro-OBD Models Only) (Cont'd)
EC-79

EXPLANATION FOR DRIVING PATTERNS FOR ªMISFIRE
NJEC0033S04Driving Pattern BNJEC0033S0401Driving pattern B means the vehicle operation as follows:
All components and systems should be monitored at least once by the OBD system.
+The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
+The B counter will be counted up when driving pattern B is satisfied without any malfunction.
+The MI will go off when the B counter reaches 3. (*2 in EC-79)
Driving Pattern CNJEC0033S0402Driving pattern C means the vehicle operation as follows:
1) The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data)±375 rpm
Calculated load value: (Calculated load value in the freeze frame data)´(1±0.1) [%]
Engine coolant temperature (T) condition:
+When the freeze frame data shows lower than 70ÉC (158ÉF), ªTº should be lower than 70ÉC (158ÉF).
+When the freeze frame data shows higher than or equal to 70ÉC (158ÉF), ªTº should be higher than or
equal to 70ÉC (158ÉF).
Example:
If the stored freeze frame data is as follows:
Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80ÉC (176ÉF)
To be satisfied with driving pattern C, the vehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70ÉC
(158ÉF)
+The C counter will be cleared when the malfunction is detected regardless of driving pattern C.
+The C counter will be counted up when driving pattern C is satisfied without the same malfunction.
+The DTC will not be displayed after C counter reaches 80.
+The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC
is stored in ECM.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
OBD System Operation Chart (With Euro-OBD Models Only) (Cont'd)
EC-80

RELATIONSHIP BETWEEN MI, DTC, 1ST TRIP DTC AND DRIVING PATTERNS EXCEPTFOR
ªMISFIRE
NJEC0033S05
SEF393SA
*1: When the same malfunction is
detected in two consecutive trips,
MI will light up.
*2: MI will go off after vehicle is driven
3 times (pattern B) without any
malfunctions.
*3: When the same malfunction is
detected in two consecutive trips,
the DTC and the freeze frame
data will be stored in ECM.*4: The DTC and the freeze frame
data will not be displayed any
longer after vehicle is driven 40
times (pattern A) without the same
malfunction.
(The DTC and the freeze frame
data still remain in ECM.)
*5: When a malfunction is detected
for the first time, the 1st trip DTCand the 1st trip freeze frame data
will be stored in ECM.
*6: 1st trip DTC will be cleared after
vehicle is driven once (pattern B)
without the same malfunction.
*7: When the same malfunction is
detected in the 2nd trip, the 1st
trip freeze frame data will be
cleared.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
OBD System Operation Chart (With Euro-OBD Models Only) (Cont'd)
EC-81