2001 NISSAN ALMERA TINO ECU

SEF184UD
On Board Diagnosis LogicNLEC1561The ECM monitors the switching frequency ratio of heated oxygen
sensors 1 (front) and 2 (rear).
A three way catalyst with high oxygen storage capacity will indicate
a low switching frequency of heated oxygen sensor 2 (rear). As
oxygen storage capacity decreases, the heated oxygen sensor 2
(rear) switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 (front) and
2 (rear) approaches a specified limit value, the three way catalyst
malfunction is diagnosed.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0420+Three way catalyst does not operate properly.
+Three way catalyst does not have enough oxygen stor-
age capacity.+Three way catalyst
+Exhaust tube
+Intake air leaks
+Injectors
+Injector leaks
+Spark plug
+Improper ignition timing
SEF847Y
SEF848Y
SEF560X
DTC Confirmation ProcedureNLEC1562CAUTION:
Always drive vehicle at a safe speed.
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
TESTING CONDITION:
+Open engine hood before conducting following proce-
dure.
+Do not hold engine speed more than specified minutes
below.
1) Turn ignition switch ªONº.
2) Select ªDTC & SRT CONFIRMATIONº then ªSRT WORK SUP-
PORTº mode with CONSULT-II.
3) Start engine.
4) Rev engine up to 3,000±500 rpm and hold it for 3 consecutive
minutes then release the accelerator pedal completely.
If ªCOMPLETEDº appears on the CONSULT-II screen, go to
step 7.
5) Wait 5 seconds at idle.
6) Rev engine up to 2,500±500 rpm and maintain it until ªINCMPº
of CATALYST changes to ªCMPLTº (it will take approximately
5 minutes.)
If not ªCMPLTº, stop engine and cool it down to less than 70ÉC
(158ÉF) and then retest from step 1.
7) Select ªSELF-DIAG RESULTSº mode with CONSULT-II.
8) Confirm that the 1st trip DTC is not detected.
If the 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-849.
DTC P0420 THREE WAY CATALYST FUNCTIONSR20DE
On Board Diagnosis Logic
EC-848

SEF074X
Overall Function CheckNLEC1563Use this procedure to check the overall function of the three way
catalyst. During this check, a 1st trip DTC might not be confirmed.
Without CONSULT-II
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeters probes between ECM terminals 62 (HO2S1
signal), 63 (HO2S2 signal) and engine ground.
4) Keep engine speed at 2,000 rpm constant under no load.
5) Make sure that the voltage switching frequency (high & low)
between ECM terminal 63 and engine ground is much less
than that of ECM terminal 62 and engine ground.
Switching frequency ratio = A/B
A: Heated oxygen sensor 2 (rear) voltage switching fre-
quency
B: Heated oxygen sensor 1 (front) voltage switching fre-
quency
This ratio should be less than 0.75.
If the ratio is greater than above, it means three way catalyst
does not operate properly.
NOTE:
If the voltage at terminal 62 does not switch periodically more
than 5 times within 10 seconds at step 4, perform trouble
diagnosis for DTC P0133 first. (See EC-729.)
Diagnostic ProcedureNLEC1564
1 CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.
OK or NG
OK©GO TO 2.
NG©Repair or replace.
DTC P0420 THREE WAY CATALYST FUNCTIONSR20DE
Overall Function Check
EC-849

SEF196Y
With CONSULT-II
1) Start engine
2) Read ªVHCL SPEED SEº in ªDATA MONITORº mode with
CONSULT-II. The vehicle speed on CONSULT-II should
exceed 10 km/h (6 MPH) when rotating wheels with suitable
gear position.
3) If NG, go to ªDiagnostic Procedureº, EC-862.
If OK, go to following step.
4) Select ªDATA MONITORº mode with CONSULT-II.
5) Warm engine up to normal operating temperature.
6) Maintain the following conditions for at least 10 consecutive
seconds.
ENG SPEED 1,600 - 3,100 rpm
COOLAN TEMP/S More than 70ÉC (158ÉF)
B/FUEL SCHDL 5.0 - 11.8 msec
Selector lever Suitable position
PW/ST SIGNAL OFF
7) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-862.
With GST
1) Lift up drive wheels.
2) Start engine.
3) Read vehicle speed sensor signal in ªMODE 1º with GST.
The vehicle speed sensor on GST should be able to exceed
10 km/h (6 MPH) when rotating wheels with suitable gear posi-
tion.
4) If NG, go to ªDiagnostic Procedureº, EC-862.
SEF607Y
No Tools
1) Lift up drive wheels.
2) Start engine.
3) Read the voltage signal between ECM terminal 86 (Vehicle
speed sensor signal) and ground with oscilloscope.
4) Verify that the oscilloscope screen shows the signal wave as
shown at ªECM terminals and Reference Valueº, EC-858.
5) If NG, go to ªDiagnostic Procedureº, EC-862.
DTC P0500 VEHICLE SPEED SENSOR (VSS)SR20DE
DTC Confirmation Procedure (Cont'd)
EC-859

3) Select ªCLSD THL/P SWº in ªDATA MONITORº mode.
If ªCLSD THL/P SWº is not available, go to step 5.
4) Check the signal under the following conditions.
Condition Signal indication
Throttle valve: Idle position ON
Throttle valve: Slightly open OFF
If the result is NG, go to ªDiagnostic Procedureº, EC-876.
If OK, go to following step.
5) Select ªDATA MONITORº mode with CONSULT-II.
SEF198Y
6) Drive the vehicle for at least 5 consecutive seconds under the
following condition.
THRTL POS SEN More than 2.3V
VHCL SPEED SE More than 4 km/h (2 MPH)
Selector lever Suitable position
Driving pattern Driving vehicle uphill (Increased engine load)
will help maintain the driving conditions
required for this test.
7) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-876.
SEF090X
Overall Function CheckNLEC1592Use this procedure to check the overall function of the closed
throttle position switch circuit. During this check, a 1st trip DTC
might not be confirmed.
Without CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Check the voltage between ECM terminal 40 (Closed throttle
position switch signal) and ground under the following condi-
tions.
Condition Voltage
At idle Battery voltage
At 2,000 rpm Approximately 0V
3) If NG, go to ªDiagnostic Procedureº, EC-876.
DTC P0510 CLOSED THROTTLE POSITION SWITCHSR20DE
DTC Confirmation Procedure (Cont'd)
EC-873

SEF174Y
PROCEDURE FOR MALFUNCTION A=NLEC1629S01With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Verify that ªCOOLAN TEMP/Sº is less than 50ÉC (122ÉF).
If the engine coolant temperature is above the range, cool
the engine down.
4) Start engine and let it idle for at least 8 seconds.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-919.
With GST
Follow the procedure ªWith CONSULT-IIº above.
SEF200Y
PROCEDURE FOR MALFUNCTION BNLEC1629S02CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:
Always perform the test at a temperature above þ10ÉC (14ÉF).
With CONSULT-II
1) Start engine and warm it up to above 80ÉC (176ÉF).
2) Select ªEGR VOL CONT/Vº in ªACTIVE TESTº mode with
CONSULT.
3) Hold engine speed at 1,500 rpm.
4) Touch ªQuº and set the EGR volume control valve opening to
50 step and check EGR TEMP SEN.
EGR TEMP SEN should decrease to less than 1.0V.
If the check result is NG, go to ªDIAGNOSTIC PROCEDUREº,
EC-919.
If the check result is OK, go to the following step.
SEF201Y
5) Turn ignition switch ªOFFº and wait at least 10 seconds then
turn ªONº.
6) Check the output voltage of ªTHRTL POS SENº (at closed
throttle position) and note it.
7) Start engine and maintain the following conditions for at least
5 consecutive seconds.
DTC P1401 EGR TEMPERATURE SENSOR (WHERE FITTED)SR20DE
DTC Confirmation Procedure (Cont'd)
EC-916

ENG SPEED 1,600 - 3,500 rpm
VHCL SPEED SE 10 km/h (6 MPH) or more
B/FUEL SCHDL 5.0 - 8.5 msec
THRTL POS SEN (X + 0.05) þ (X + 0.87)V
X = Voltage value measured at step 6
Selector lever Suitable position
8) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-919.
SEF066X
With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds, then
turn ªONº.
3) Select ªMODE 1º with GST and maintain the following condi-
tions for at least 5 consecutive seconds.
Engine speed 1,600 - 3,500 rpm
Vehicle speed 10 km/h (6 MPH) or more
Voltage between ECM terminal
92 and ground0.86 - 2.0V
Selector lever Suitable position
4) Select ªMODE 7º with GST
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-919.
DTC P1401 EGR TEMPERATURE SENSOR (WHERE FITTED)SR20DE
DTC Confirmation Procedure (Cont'd)
EC-917

SEF213Y
2) Select ªP/N POSI SWº in ªDATA MONITORº mode with CON-
SULT-II. Then check the ªP/N POSI SWº signal under the fol-
lowing conditions.
Position (Selector lever) Known-good signal
ªNº and ªPº position ON
Except the above position OFF
If NG, go to ªDiagnostic Procedureº, EC-935.
If OK, go to following step.
3) Select ªDATA MONITORº mode with CONSULT-II.
4) Start engine and warm it up to normal operating temperature.
5) Maintain the following conditions for at least 50 consecutive
seconds.
ENG SPEED 1,250 - 3,350 rpm
COOLAN TEMP/S More than 70ÉC (158ÉF)
B/FUEL SCHDL 3.5 - 14.0 msec
VHCL SPEED SE 64 - 130 km/h (40 - 81 MPH)
Selector lever Suitable position
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-935.
SEF137X
Overall Function CheckNLEC1652Use this procedure to check the overall function of the park/neutral
position switch circuit. During this check, a 1st trip DTC might not
be confirmed.
Without CONSULT-II
1) Turn ignition switch ªONº.
2) Check voltage between ECM terminal 42 (PNP switch signal)
and body ground under the following conditions.
Condition (Gear position) Voltage (V) (Known good data)
ªPº and ªNº position Approx. 0
Except the above positionBATTERY VOLTAGE
(11 - 14V)
3) If NG, go to ªDiagnostic Procedureº, EC-935.
DTC P1706 PARK/NEUTRAL POSITION (PNP) SWITCHSR20DE
DTC Confirmation Procedure (Cont'd)
EC-932

Diagnostic ProcedureNLEC1801
1 CHECK OVERALL FUNCTION-I
1. Start engine and drive the vehicle at over 70 km/h (43 MPH) for 2 consecutive minutes.
2. Stop vehicle and keep the engine running.
3. Set voltmeter probes between ECM terminals 63 [HO2S2 (B1) signal] and ground.
4. Check the voltage while revving up to 4,000 rpm under no load at least 10 times.
(Depress and release the accelerator pedal as quickly as possible.)
SEF240Z
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK OVERALL FUNCTION-II
Keep engine at idle for 10 minutes, then check the voltage between ECM terminal 63 and ground, or check the voltage
when coasting at 80 km/h (50 MPH) in ªDº position with ªSPORTS MODE SWº OFF.
SEF240Z
OK or NG
OK©INSPECTION END
NG©GO TO 3.
HEATED OXYGEN SENSOR 2 (REAR)SR20DE
Diagnostic Procedure
EC-959