NISSAN PRIMERA 1999 Electronic Repair Manual

Component DescriptionNCEC0171The heated oxygen sensor 2 (rear) (Rear HO2S), after three way
catalyst, monitors 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
NCEC0172Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
IEngine: 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 ValueNCEC0173Specification data are reference values and are measured between each terminal and 48 (ECM ground).
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
63 LHeated oxygen sensor 2
(rear)[Engine is running]
IAfter warming up to normal operating temperature
and revving engine from idle to 2,000 rpm0 - Approximately 1.0V
On Board Diagnosis LogicNCEC0174The heated oxygen sensor 2 (rear) has a much longer switching
time between rich and lean than the heated oxygen sensor 1
(front). The oxygen storage capacity before the three way catalyst
causes the longer switching time. To judge the malfunctions of
heated oxygen sensor 2 (rear), ECM monitors whether or not the
voltage is too high during various driving conditions such as fuel-
cut.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0140
0140IAn excessively high voltage from the sensor is sent to
ECM.IHarness or connectors
(The sensor circuit is open or shorted.)
IHeated oxygen sensor 2 (rear)
SEF327R
SEF305U OK NG
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
Component Description
EC-201

DTC Confirmation ProcedureNCEC0175NOTE:
If ªDTC Confirmation Procedure º has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
3) Stop vehicle with engine running.
4) Let engine idle for 1 minute.
5) Maintain the following conditions for at least 5 consecutive
seconds.
ENG SPEED 1,650 - 3,600 rpm (CVT)
1,500 - 3,600 rpm (M/T)
VHCL SPEED SE 68 - 130 km/h (42 - 81 MPH)
B/FUEL SCHDL 3.2 - 15.0 msec (CVT)
3.2 - 13.5 msec (M/T)
COOLAN TEMP/S 70 - 100ÉC (158 - 212ÉF)
Selector lever Suitable position
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
SR-204.
Overall Function CheckNCEC0176Use this procedure to check the overall function of the heated oxy-
gen sensor 2 (rear) circuit. 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 voltmeter probes between ECM terminals 63 (Heated oxy-
gen sensor 2 (rear) signal) and engine ground.
4) Check the voltage after revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be below 2V during this procedure.
5) If NG, go to ªDiagnostic Procedureº, EC-SR-204.
NEF102A
SEF032X
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
DTC Confirmation Procedure
EC-202

Wiring DiagramNCEC0177
YEC086A
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
Wiring Diagram
EC-203

Diagnostic ProcedureNCEC0178
1 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF202X
©GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect heated oxygen sensor 2 (rear) harness connector and ECM harness connector.
SEF209X2. Check harness continuity between ECM terminal 63 and heated oxygen sensor 2 (rear) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Check harness continuity between ECM terminal 63 (or terminal 2) and ground.
Continuity should not exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the harness for open or short between heated oxygen sensor 2 (rear) and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
4 CHECK GROUND CIRCUIT
1. Check harness continuity between heated oxygen sensor 2 (rear) harness connector terminal 4 and engine ground.
Refer to wiring diagram.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
Intake manifold
collector
Engine
ground
Heated oxygen sensor 2
(rear) harness connector
Heated oxygen
sensor 2 (rear)
Front exhaust tube
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
Diagnostic Procedure
EC-204

Component InspectionNCEC0179REAR HEATED OXYGEN SENSORNCEC0179S01With 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) Select ªFUEL INJECTIONº in ªACTIVE TESTº mode, and
select ªHO2S2 (B1)º as the monitor item with CONSULT-II.
4) Check ªHO2S2 (B1)º at idle speed when adjusting ªFUEL
INJECTIONº to  25%.
ªHO2S2 (B1)º should be above 0.48V at least once when
the ªFUEL INJECTIONº is +25%.
ªHO2S2 (B1)º should be below 0.43V at least once when
the ªFUEL INJECTIONº is þ25%.
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.
5 CHECK HARNESS CONNECTOR
Check heated oxygen sensor 2 (rear) harness connector for water.
Water should not exist.
OK or NG
OK©GO TO 6.
NG©Repair or replace harness connector.
6 CHECK HEATED OXYGEN SENSOR 2 (REAR)
Refer to ªComponent Inspectionº, EC-SR-205.
OK or NG
OK©GO TO 7.
NG©Replace heated oxygen sensor 2 (rear).
7 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-SR-114.
©INSPECTION END
SEF662Y
SEF989R (Reference data)
The voltage should be above
0.48V at least one time.
The voltage should be below
0.43V at least one time.
x0.01V
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
Component Inspection
EC-205

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 voltmeter probes between ECM terminals 63 (Heated oxy-
gen sensor 2 (rear) signal) and engine ground.
4) Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.48V at least once.
If the voltage is above 0.48V at step 4, step 5 is not nec-
essary.
5) Check the voltage when revving up to 6,000 rpm under no
load. Or keep vehicle at idling for 10 minutes, then check the
voltage. Or check the voltage when coasting from 80 km/h (50
MPH) in 3rd gear position (M/T), D position with ªSPORTS
MODE SWº OFF or without ªMANUAL MODEº (CVT).
The voltage should be below 0.43V at least once.
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.
SEF032X
DTC P0140 HEATED OXYGEN SENSOR 2
(REAR) (HIGH VOLTAGE)SR20DE
Component Inspection (Cont'd)
EC-206

DescriptionNCEC0180SYSTEM DESCRIPTIONNCEC0180S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor Engine speedHeated oxy-
gen sensor
2 (rear)
heater con-
trolHeated oxygen sensor 2 (rear)
heater
The ECM performs ON/OFF control of the heated oxygen sensor 2 (rear) heater corresponding to the engine
speed.
OPERATIONNCEC0180S02
Engine condition Heated oxygen sensor 2 (rear) heater
Engine stopped OFF
Engine is running below 3,600 rpm. [After driving for 2 minutes at a speed of 70 km/h
(43 MPH) or more]ON
CONSULT-II Reference Value in Data Monitor
Mode
NCEC0181Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)IEngine speed: Below 3,600 rpm [After driving for 2 minutes at a
speed of 70 km/h (43 MPH) or more]ON
IIgnition switch ON (Engine stopped) OFF
ECM Terminals and Reference ValueNCEC0182Specification data are reference values and are measured between each terminal and 48 (ECM ground).
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
3 W/RHeated oxygen sensor 2
(rear) heater[Engine is running]
IBelow 3,600 rpm [After driving for 2 minutes at a
speed of 70 km/h (43 MPH) or more]Approximately 0.7V
[Ignition switch ªONº]
IEngine stoppedBATTERY VOLTAGE
(11 - 14V)
On Board Diagnosis LogicNCEC0183
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0141
0141IThe current amperage in the heated oxygen sensor 2
(rear) heater circuit is out of the normal range.
(An improper voltage drop signal is sent to ECM through
the heated oxygen sensor 2 (rear) heater.)IHarness or connectors
(The heated oxygen sensor 2 (rear) heater cir-
cuit is open or shorted.)
IHeated oxygen sensor 2 (rear) heater
DTC P0141 HEATED OXYGEN SENSOR 2 (REAR) HEATERSR20DE
Description
EC-207

DTC Confirmation ProcedureNCEC0184NOTE:
If ªDTC Confirmation Procedure º has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is in between 10.5V and 16V at idle.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
3) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
SR-210.
With GST
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
4) Select ªMODE 3º with GST.
5) If DTC is detected, go to ªDiagnostic Procedureº, EC-SR-210.
When using GST, ªDTC Confirmation Procedure º should be
performed twice as much as when using CONSULT-II or ECM
(Diagnostic Test Mode II) because GST cannot display MODE
7 (1st trip DTC) concerning this diagnosis. Therefore, using
CONSULT-II or ECM (Diagnostic Test Mode II) is
recommended.
NEF103A
DTC P0141 HEATED OXYGEN SENSOR 2 (REAR) HEATERSR20DE
DTC Confirmation Procedure
EC-208

Wiring DiagramNCEC0185
YEC087A
DTC P0141 HEATED OXYGEN SENSOR 2 (REAR) HEATERSR20DE
Wiring Diagram
EC-209

Diagnostic ProcedureNCEC0186
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 2 (rear) harness connector.
SEF209X3. Turn ignition switch ªONº.
4. Check voltage between terminal 4 and ground.
SEF047XVoltage: Battery voltage
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors M50, F104 (M81, F115 for CVT models)
IHarness for open or short between heated oxygen sensor 2 (rear) and fuse
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between heated oxygen sensor 2 (rear) harness connector terminal 1 and ECM terminal 3.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©GO TO 4.
4 DETECT MALFUNCTIONING PART
Check the harness for open or short between heated oxygen sensor 2 (rear) heater and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
Heated oxygen sensor 2
(rear) harness connector
Heated oxygen
sensor 2 (rear)
Front exhaust
tube
DTC P0141 HEATED OXYGEN SENSOR 2 (REAR) HEATERSR20DE
Diagnostic Procedure
EC-210