2001 NISSAN ALMERA engine

7 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-455.
OK or NG
OK©GO TO 8.
NG©Replace heated oxygen sensor 1 (front).
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
SEF646Y
SEF647Y
Component InspectionNJEC1222HEATED OXYGEN SENSOR 1 (FRONT)NJEC1222S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Select ªMANU TRIGº in ªDATA MONITORº mode, and select
ªHO2S1 (B1)º and ªHO2S1 MNTR (B1)º.
3) Hold engine speed at 2,000 rpm under no load during the fol-
lowing steps.
4) Touch ªRECORDº on CONSULT-II screen.
5) Check the following.
+ªHO2S1 MNTR (B1)º in ªDATA MONITORº mode changes from
ªRICHº to ªLEANº to ªRICHº 5 times in 10 seconds.
5 times (cycles) are counted as shown below:
R = ªHO2S1 MNTR (B1)º, ªRICHº
L = ªHO2S1 MNTR (B1)º, ªLEANº
+ªHO2S1 (B1)º voltage goes above 0.6V at least once.
+ªHO2S1 (B1)º voltage goes below 0.3V at least once.
+ªHO2S1 (B1)º voltage never exceeds 1.0V.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
HEATED OXYGEN SENSOR 1 (FRONT)QG
Diagnostic Procedure (Cont'd)
EC-455

SEF648Y
SEF011X
Without CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal 62 (HO2S1 sig-
nal) and engine ground.
3) Check the following with engine speed held at 2,000 rpm con-
stant under no load.
+The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V more
than 5 times within 10 seconds.
+The maximum voltage is over 0.6V at least one time.
+The minimum voltage is below 0.3V at least one time.
+The voltage never exceeds 1.0V.
1 time: 0 - 0.3V®0.6 - 1.0V®0 - 0.3V
2 times: 0 - 0.3V®0.6 - 1.0V®0 - 0.3V®0.6 - 1.0V®0-
0.3V
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
HEATED OXYGEN SENSOR 1 (FRONT)QG
Component Inspection (Cont'd)
EC-456

DescriptionNJEC1223SYSTEM DESCRIPTIONNJEC1223S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speedHeated
oxygen
sensor 1
heater
(front) con-
trolHeated oxygen sensor 1 heater
(front)
The ECM performs ON/OFF control of the heated oxygen sensor 1 heater (front) corresponding to the engine
operating condition.
OPERATIONNJEC1223S02
Engine speed Heated oxygen sensor 1 heater (front)
Above 3,200 rpm OFF
Below 3,200 rpm ON
CONSULT-II Reference Value in Data Monitor
Mode
NJEC1224Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)+Engine speed: Below 3,200 rpm ON
+Engine speed: Above 3,200 rpm OFF
ECM Terminals and Reference ValueNJEC1225Specification 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)
4 R/BHeated oxygen sensor 1
heater (front)[Engine is running]
+Engine speed is below 3,200 rpm.Approximately 0V
[Engine is running]
+Engine speed is above 3,200 rpm.BATTERY VOLTAGE
(11 - 14V)
HEATED OXYGEN SENSOR 1 HEATER (FRONT)QG
Description
EC-457

Wiring DiagramNJEC1228SEDAN MODELS AND HATCHBACK MODELS WITH
ECM IN ENGINE COMPARTMENT
NJEC1228S03
HEC852
HEATED OXYGEN SENSOR 1 HEATER (FRONT)QG
Wiring Diagram
EC-458

Diagnostic ProcedureNJEC1229
1 CHECK OVERALL FUNCTION
1. Turn ignition switch ªONº.
2. Set the tester probe between ECM terminals 4 [HO2S1 Heater (front) signal] and ground.
3. Start engine and let it idle.
4. Check the voltage under the following conditions.
SEF239Z
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 1 (front) harness connector.
SEF012XA
3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and ground with CONSULT-II or tester.
SEF934X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
HEATED OXYGEN SENSOR 1 HEATER (FRONT)QG
Diagnostic Procedure
EC-460

SEF327R
Component DescriptionNJEC1231The heated oxygen sensor 2 (rear), after three way catalyst, moni-
tors the oxygen level in the exhaust gas.
Even if switching characteristics of the heated oxygen sensor 1
(front) are shifted, the air fuel ratio is controlled to stoichiometric,
by the signal from the heated oxygen sensor 2 (rear).
This sensor is made of ceramic zirconia. The zirconia generates
voltage from approximately 1V in richer conditions to 0V in leaner
conditions.
Under normal conditions the heated oxygen sensor 2 (rear) is not
used for engine control operation.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC1232Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
+Engine: After warming upRevving engine from idle to 3,000
rpm0 - 0.3V¨Approx. 0.6 - 1.0V
HO2S2 MNTR
(B1)LEAN¨RICH
ECM Terminals and Reference ValueNJEC1233Specification 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)
63 LHeated oxygen sensor 2
(rear)[Engine is running]
+After warming up to normal operating tempera-
ture and engine speed is 3,000 rpm0 - Approximately 1.0V
HEATED OXYGEN SENSOR 2 (REAR)QG
Component Description
EC-462

Wiring DiagramNJEC1237SEDAN MODELS AND HATCHBACK MODELS WITH
ECM IN ENGINE COMPARTMENT
NJEC1237S03
HEC853
HEATED OXYGEN SENSOR 2 (REAR)QG
Wiring Diagram
EC-463

Diagnostic ProcedureNJEC1238
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 3rd gear (M/T), ªDº position with ªODº OFF (A/T).
SEF240Z
OK or NG
OK©INSPECTION END
NG©GO TO 3.
HEATED OXYGEN SENSOR 2 (REAR)QG
Diagnostic Procedure
EC-465