2001 NISSAN PICK-UP check engine light

14 CHECK IGNITION TIMING
Without CONSULT-II
1. Warm up engine to normal operating temperature.
2. Stop engine and disconnect throttle position sensor harness connector.
SEF265S
3. Start engine.
4. Rev engine (2,000 to 3,000 rpm) two or three times under no-load and then run engine at idle speed.
5. Check ignition timing at idle using timing light.
SEF320V
Ignition timing:
15ɱ2É BTDC
OK or NG
OK©GO TO 15.
NG©1. Adjust ignition timing by turning distributor. Refer to ªIdle Speed/Ignition Timing/Idle
Mixture Ratio Adjustmentº, EC-3035.
2. GO TO 15.
15 CHECK BASE IDLE SPEED
Without CONSULT-II
Make sure that engine speed falls to the following speed.
650±50 rpm
OK or NG
OK©GO TO 16.
NG©1. Adjust base idle speed by turning idle speed adjusting screw. Refer to ªIdle Speed/
Ignition Timing/Idle Mixture Ratio Adjustmentº, EC-3035.
2. GO TO 16.
TROUBLE DIAGNOSIS Ð BASIC
INSPECTION
KA24DE (EURO OBD)
Basic Inspection
EC-3095

SEF893J
Component DescriptionNEEC0050The mass air flow sensor is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. It consists of a hot wire that is supplied with electric
current from the ECM. The temperature of the hot wire is controlled
by the ECM a certain amount. The heat generated by the hot wire
is reduced as the intake air flows around it. The more air, the
greater the heat loss.
Therefore, the ECM must supply more electric current to maintain
the temperature of the hot wire as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor
Mode
NEEC0051Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 0.9 - 1.8V
2,500 rpm 1.9 - 2.3V
CAL/LD VALUE+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 9.5 - 34.0%
2,500 rpm 13.9 - 24.9%
MASS AIRFLOW+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 0.9 - 5.8 g´m/s
2,500 rpm 7.5 - 13.2 g´m/s
ECM Terminals and Reference ValueNEEC0052Specification 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 result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
54 L Mass air flow sensor[Engine is running]
+Warm-up condition
+Idle speed0.9 - 1.8V
[Engine is running]
+Warm-up condition
+Engine speed is 2,500 rpm1.9 - 2.3V
55 PMass air flow sensor
ground[Engine is running]
+Warm-up condition
+Idle speedApproximately 0V
On Board Diagnosis LogicNEEC0053
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0101
0101A) A high voltage from the sensor is sent to ECM under
light load driving condition.+Harness or connectors
(The sensor circuit is open or shorted.)
+Mass air flow sensor
DTC P0101 MAF SENSORKA24DE (EURO OBD)
Component Description
EC-3143

DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0101
0101B) A low voltage from the sensor is sent to ECM* under
heavy load driving condition.+Harness or connectors
(The sensor circuit is open or shorted.)
+Intake air leaks
+Mass air flow sensor
*: When this malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
FAIL-SAFE MODENEEC0053S01
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuitEngine speed will not rise more than 2,400 rpm due to the fuel
cut.
DTC Confirmation ProcedureNEEC0054CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
SEF174Y
PROCEDURE FOR MALFUNCTION ANEEC0054S03NOTE:
If engine will not start or stops soon, wait at least 10 seconds
with engine stopped (Ignition switch ªONº) instead of running
engine at idle speed.
With CONSULT-II
1) Turn ignition switch ON.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and warm it up to normal operating temperature.
4) Run engine for at least 10 seconds at idle speed.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3147.
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0101 MAF SENSORKA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3144

DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0102
0102An excessively low voltage from the sensor is sent to
ECM* when engine is running.+Harness or connectors
(The sensor circuit is open or shorted.)
+Intake air leaks
+Mass air flow sensor
*: When this malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
FAIL-SAFE MODENEEC1551S01
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuitEngine speed will not rise more than 2,400 rpm due to the fuel
cut.
DTC Confirmation ProcedureNEEC1552CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
SEF058Y
PROCEDURE FOR DTC P0103NEEC1552S01With CONSULT-II
1) Turn ignition switch ON.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 6 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3155.
If 1st trip DTC is not detected, go to next step.
5) Start engine and let it idle for at least 6 seconds.
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3155.
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3152

ECM Terminals and Reference Value=NEEC0081Specification 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 result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
23 G Throttle position sensor[Ignition switch ON]
+Warm-up condition
+Accelerator pedal fully released0.2 - 0.8V
[Ignition switch ON]
+Accelerator pedal fully depressed3.5 - 4.5V
42 G/B Sensors' power supply[Ignition switch ON]Approximately 5V
43 B Sensors' ground[Engine is running]
+Idle speedApproximately 0V
On Board Diagnosis LogicNEEC0082
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0121
0121A) A high voltage from the sensor is sent to ECM
under light load driving condition.+Harness or connectors
(The throttle position sensor circuit is open or
shorted.)
+Throttle position sensor
+Fuel injector
+Camshaft position sensor
+Mass air flow sensor
B) A low voltage from the sensor is sent to ECM under
heavy load driving condition.+Harness or connectors
(The throttle position sensor circuit is open or
shorted.)
+Intake air leaks
+Throttle position sensor
DTC P0121 TP SENSORKA24DE (EURO OBD)
ECM Terminals and Reference Value
EC-3171

On Board Diagnosis LogicNEEC0188With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensor 1. The ECM
calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MI (2 trip detection logic).
Sensor Input Signal to ECMECM func-
tionActuator
Heated oxygen sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injec-
tion & mix-
ture ratio
controlInjectors
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0171
0171+Fuel injection system does not operate properly.
+The amount of mixture ratio compensation is too large.
(The mixture ratio is too lean.)+Intake air leaks
+Heated oxygen sensor 1
+Injectors
+Exhaust gas leaks
+Incorrect fuel pressure
+Lack of fuel
+Mass air flow sensor
+Incorrect PCV hose connection
SEF215Z
SEF058Y
DTC Confirmation ProcedureNEEC0189NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch OFF and wait at least 5 seconds.
3) Turn ignition switch ON and select ªSELF-LEARNING CONTº
in ªWORK SUPPORTº mode with CONSULT-II.
4) Clear the self-learning control coefficient by touching ªCLEARº.
5) Select ªDATA MONITORº mode with CONSULT-II.
6) Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0171 should be detected at this stage, if a
malfunction exists. If so, go to ªDiagnostic Procedureº,
EC-3240.
7) If it is difficult to start engine at step 6, the fuel injection sys-
tem has a malfunction.
8) Crank engine while depressing accelerator pedal. If engine
starts, go to ªDiagnostic Procedureº, EC-3240. If engine does
not start, visually check for exhaust and intake air leak.
AEC131A
With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch OFF and wait at least 5 seconds.
3) Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 3 seconds at idle speed.
4) Stop engine and reconnect mass air flow sensor harness con-
nector.
5) Select ªMODE 7º with GST. Make sure DTC P0102 is detected.
6) Select ªMODE 4º with GST and erase the DTC P0102.
7) Start engine again and run it for at least 10 minutes at idle
speed.
DTC P0171 FUEL INJECTION SYSTEM
FUNCTION
KA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3237

On Board Diagnosis LogicNEEC0192With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensor 1. The ECM
calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MI (2 trip detection logic).
Sensor Input Signal to ECMECM func-
tionActuator
Heated oxygen sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injec-
tion & mix-
ture ratio
controlInjectors
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0172
0172+Fuel injection system does not operate properly.
+The amount of mixture ratio compensation is too large.
(The mixture ratio is too rich.)+Heated oxygen sensor 1
+Injectors
+Exhaust gas leaks
+Incorrect fuel pressure
+Mass air flow sensor
SEF215Z
SEF058Y
DTC Confirmation ProcedureNEEC0193NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch OFF and wait at least 5 seconds.
3) Turn ignition switch ON and select ªSELF-LEARNING CONTº
in ªWORK SUPPORTº mode with CONSULT-II.
4) Clear the self-learning control coefficient by touching ªCLEARº.
5) Select ªDATA MONITORº mode with CONSULT-II.
6) Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0172 should be detected at this stage, if a
malfunction exists. If so, go to ªDiagnostic Procedureº,
EC-3247.
7) If it is difficult to start engine at step 6, the fuel injection sys-
tem has a malfunction.
8) Crank engine while depressing accelerator pedal. If engine
starts, go to ªDiagnostic Procedureº, EC-3247. If engine does
not start, remove ignition plugs and check for fouling, etc.
AEC131A
With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch OFF and wait at least 5 seconds.
3) Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 3 seconds at idle speed.
4) Stop engine and reconnect mass air flow sensor harness con-
nector.
5) Select ªMODE 7º with GST. Make sure 1st trip DTC P0102 is
detected.
6) Select ªMODE 4º with GST and erase the 1st trip DTC P0102.
DTC P0172 FUEL INJECTION SYSTEM
FUNCTION
KA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3244

On Board Diagnosis LogicNEEC0202When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the CKP
sensor signal to vary, the ECM can determine that a misfire is occurring.
Sensor Input Signal to ECM ECM function
Crankshaft position sensor (OBD) Engine speed On board diagnosis of misfire
The misfire detection logic consists of the following two conditions.
1. One Trip Detection Logic (Three Way Catalyst Damage)
On the first trip that a misfire condition occurs that can damage the three way catalyst (TWC) due to
overheating, the MI will blink.
When a misfire condition occurs, the ECM monitors the CKP sensor signal every 200 engine revolutions
for a change.
When the misfire condition decreases to a level that will not damage the TWC, the MI will turn off.
If another misfire condition occurs that can damage the TWC on a second trip, the MI will blink.
When the misfire condition decreases to a level that will not damage the TWC, the MI will remain on.
If another misfire condition occurs that can damage the TWC, the MI will begin to blink again.
2. Two Trip Detection Logic (Exhaust quality deterioration)
For misfire conditions that will not damage the TWC (but will affect vehicle emissions), the MI will only light
when the misfire is detected on a second trip. During this condition, the ECM monitors the CKP sensor
signal every 1,000 engine revolutions.
A misfire malfunction can be detected on any one cylinder or on multiple cylinders.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0300
0300+Multiple cylinders misfire.+Improper spark plug
+Insufficient compression
+Incorrect fuel pressure
+The injector circuit is open or shorted
+Injectors
+Intake air leak
+The ignition secondary circuit is open or shorted
+Lack of fuel
+Drive plate/Flywheel
+Heated oxygen sensor 1
+Incorrect distributor rotor P0301
0301+No. 1 cylinder misfires.
P0302
0302+No. 2 cylinder misfires.
P0303
0303+No. 3 cylinder misfires.
P0304
0304+No. 4 cylinder misfires.
SEF174Y
DTC Confirmation ProcedureNEEC0203CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
With CONSULT-II
1) Turn ignition switch ON, and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and warm it up to normal operating temperature.
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE, MULTIPLE CYLINDER
MISFIRE
KA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3251