2001 NISSAN PICK-UP ECU

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.
NVIS (Nissan Vehicle Immobilizer System Ð
NATS)
NEEC1601
SEF515Y
+If the security indicator lights up with the ignition switch in the ªONº position or ªNATS MALFUNC-
TIONº is displayed on ªSELF-DIAG RESULTSº screen, perform self-diagnostic results mode with
CONSULT-II using NATS program card. Refer to ªNVIS (Nissan Vehicle Immobilizer System Ð
NATS)º in EL section.
+Confirm no self-diagnostic results of NVIS (NATS) is displayed before touching ªERASEº in ªSELF-
DIAG RESULTSº mode with CONSULT-II.
+When replacing ECM, initialization of NVIS (NATS) system and registration of all NVIS (NATS) igni-
tion 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 NVIS (NATS)
initialization and NVIS (NATS) ignition key ID registration, refer to CONSULT-II operation manual,
IVIS/NVIS.
Malfunction Indicator (MI)
DESCRIPTIONNEEC0032
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 section, ªWARNING LAMPSº or see EC-3396.
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 FunctionNEEC0032S07The on board diagnostic system has the following four functions.
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION
KA24DE (EURO OBD)
Emission-related Diagnostic Information
EC-3061

Diagnostic Test
ModeKEY and ENG.
StatusFunction Explanation of Function
Mode I Ignition switch in
ªONº 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.
Engine running
MALFUNCTION WARNING This is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MI will light up to inform the driver
that a malfunction has been detected. The following mal-
functions will light up or blink the MI in the 1st trip.
+ªMisfire (Possible three way catalyst damage)º
+ªClosed loop controlº
+Fail-safe mode
Mode II Ignition switch in
ªONº position
Engine stopped
SELF-DIAGNOSTIC RESULTS This function allows DTCs and 1st trip DTCs to be read.
Engine running
HEATED OXYGEN SENSOR 1
MONITORThis function allows the fuel mixture condition (lean or
rich), monitored by heated oxygen sensor 1, to be read.
MI Flashing without DTCNEEC0032S0701If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM diag-
nostic test mode. How to Switch Diagnostic Test Mode.
How to switch the diagnostic test (function) modes, and details of the above functions are described later. How
to Switch Diagnostic Test Mode.
The following emission-related diagnostic information is cleared when the ECM memory is erased.
1. Diagnostic trouble codes
2. 1st trip diagnostic trouble codes
3. Freeze frame data
4. 1st trip freeze frame data
5. System readiness test (SRT) codes
6. Test values
7. Others
How to Switch Diagnostic Test ModeNEEC0032S08NOTE:
+It is better to count the time accurately with a clock.
+It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
+Always ECM returns to Diagnostic Test Mode I after ignition switch is turned ªOFFº.
How to Set Diagnostic Test Mode II (Self-diagnostic Results)
NEEC0032S08011. Confirm that accelerator pedal is fully released, turn ignition switch ªONº and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
1) Fully depress the accelerator pedal.
2) Fully release the accelerator pedal.
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION
KA24DE (EURO OBD)
Malfunction Indicator (MI)
EC-3062

SEC687C
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 1,000th-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 later
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 ªTROUBLE DIAGNOSIS Ð INDEXº, EC-3009.)
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
NEEC0032S1101The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to How
to Switch Diagnostic Test Mode.
+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 MonitorNEEC0032S12In this mode, the MI displays the condition of the fuel mixture (lean or rich) which is monitored by the heated
oxygen sensor 1.
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 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 ChartNEEC0033RELATIONSHIP BETWEEN MI, DTC, 1ST TRIP DTC AND DETECTABLE ITEMSNEEC0033S01+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-3049.
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION
KA24DE (EURO OBD)
Malfunction Indicator (MI)
EC-3064

+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 CHARTNEEC0033S02
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-3067.
For details about patterns ªAº and ªBº under ªOtherº, see EC-3069.
*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
DESCRIPTION
KA24DE (EURO OBD)
OBD System Operation Chart
EC-3065

RELATIONSHIP BETWEEN MI, DTC, 1ST TRIP DTC AND DRIVING PATTERNS FOR
ªMISFIREº , ªFUEL INJECTION SYSTEMº
=NEEC0033S03
SEF392SC
*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
DESCRIPTION
KA24DE (EURO OBD)
OBD System Operation Chart
EC-3066

RELATIONSHIP BETWEEN MI, DTC, 1ST TRIP DTC AND DRIVING PATTERNS EXCEPTFOR
ªMISFIRE º, ªFUEL INJECTION SYSTEMº
NEEC0033S05
SEF393SC
*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
DESCRIPTION
KA24DE (EURO OBD)
OBD System Operation Chart
EC-3068

LEC106A
ECM Terminals and Reference ValueNEEC0044PREPARATIONNEEC0044S011. ECM is located behind the instrument lower cover. For this
inspection:
+Remove instrument lower cover.
AEC913
2. Remove ECM harness protector.
SEF367I
3. Perform all voltage measurements with the connector con-
nected. Extend tester probe as shown to perform tests easily.
+Open harness securing clip to make testing easier.
+Use extreme care not to touch 2 pins at one time.
+Data is for comparison and may not be exact.
TROUBLE DIAGNOSIS Ð GENERAL
DESCRIPTION
KA24DE (EURO OBD)
ECM Terminals and Reference Value
EC-3110

DescriptionNEEC0045Intermittent incidents (I/I) may occur. In many cases, the problem resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the custom-
er's complaint often do not recur on DTC (1st trip) visits. Realize also that the most frequent cause of I/I
occurrences is poor electrical connections. Because of this, the conditions under which the incident occurred
may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may not indi-
cate the specific problem area.
COMMON I/I REPORT SITUATIONSNEEC0045S01
STEP in Work Flow Situation
IIThe CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than ª0º or
ª1tº.
III The symptom described by the customer does not recur.
IV (1st trip) DTC data does not appear during the DTC CONFIRMATION PROCEDURE.
VI The TROUBLE DIAGNOSIS for PXXXX does not indicate the problem area.
Diagnostic ProcedureNEEC0046
1 INSPECTION START
Erase (1st trip) DTCs. Refer to ªHOW TO ERASE EMISSION-RELATED INFORMATIONº, EC-3060.
©GO TO 2.
2 CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection. Refer to ªCircuit Inspectionº, ªGROUND INSPECTIONº, GI sec-
tion.
OK or NG
OK©GO TO 3.
NG©Repair or replace.
3 SEARCH FOR ELECTRICAL INCIDENT
Perform ªIncident Simulation Testsº, GI section.
OK or NG
OK©INSPECTION END
NG©Repair or replace.
TROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENT
KA24DE (EURO OBD)
Description
EC-3123