Page 857 of 3051

SEF032X
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 (HO2S2 sig-
nal) 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 0.68V at least once.
If the voltage is above 0.68V 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.
The voltage should be below 0.56V 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.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
HEATED OXYGEN SENSOR 2 (REAR)QG18DE
Component Inspection (Cont'd)
EC-432
Page 858 of 3051

DescriptionNLEC1240SYSTEM DESCRIPTIONNLEC1240S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speedHeated
oxygen
sensor 2
heater
(rear) con-
trolHeated oxygen sensor 2 heater
(rear)
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater (rear) corresponding to the engine
speed.
OPERATIONNLEC1240S02
Engine condition Heated oxygen sensor 2 heater (rear)
Engine stopped OFF
Engine is running. Engine speed below 3,600 rpm [After
driving for 2 minutes at a speed of 70
km/h (43 MPH) or more]ON
Engine speed above 3,600 rpm OFF
CONSULT-II Reference Value in Data Monitor
Mode
NLEC1241Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)+Engine speedBelow 3,600 rpm [After driving for 2 minutes at a
speed of 70 km/h (43 MPH) or more]ON
Above 3,600 rpm OFF
+Ignition switch ON (Engine stopped) OFF
ECM Terminals and Reference ValueNLEC1242Specification 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)
3 W/RHeated oxygen sensor 2
heater (rear)[Engine is running]
+Engine speed is below 3,600 rpm [After driving
for 2 minutes at a speed of 70 km/h (43 MPH) or
more]0-1V
[Engine is running]
+Engine speed is above 3,600 rpm
BATTERY VOLTAGE
(11 - 14V)
[Ignition switch ªONº]
+Engine stopped
HEATED OXYGEN SENSOR 2 HEATER (REAR)QG18DE
Description
EC-433
Page 859 of 3051
Wiring DiagramNLEC1245MODELS WITH ECM IN ENGINE COMPARTMENTNLEC1245S03
YEC747
HEATED OXYGEN SENSOR 2 HEATER (REAR)QG18DE
Wiring Diagram
EC-434
Page 860 of 3051
MODELS WITH ECM IN CABINNLEC1245S04
YEC896
HEATED OXYGEN SENSOR 2 HEATER (REAR)QG18DE
Wiring Diagram (Cont'd)
EC-435
Page 861 of 3051
Diagnostic ProcedureNLEC1246
1 CHECK OVERALL FUNCTION
Without CONSULT-II
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 the voltmeter probe between ECM terminals 3 [HO2S2 HTR (B1) signal] and ground.
4. Check the voltage under the following conditions.
SEF241Z
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 2 (rear) harness connector.
SEF639Z
3. Turn ignition switch ªONº.
4. Check voltage between terminal 2 and ground.
SEF218W
Voltage: Battery voltage
OK or NG
OK©GO TO 4.
NG©GO TO 3.
HEATED OXYGEN SENSOR 2 HEATER (REAR)QG18DE
Diagnostic Procedure
EC-436
Page 862 of 3051

3 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors F38, M50 (where fitted)
+Harness connectors M72, F44 (where fitted)
+Harness for open or short between heated oxygen sensor 2 (rear) and fuse
+10A fuse
©Repair harness or connectors.
4 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between heated oxygen sensor 2 (rear) harness connector terminal 3 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 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the harness for open or short between heated oxygen sensor 2 heater (rear) and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK HEATED OXYGEN SENSOR 2 HEATER (REAR)
Refer to ªComponent Inspectionº, EC-438.
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-145.
©INSPECTION END
HEATED OXYGEN SENSOR 2 HEATER (REAR)QG18DE
Diagnostic Procedure (Cont'd)
EC-437
Page 863 of 3051
SEF221W
Component InspectionNLEC1247HEATED OXYGEN SENSOR 2 HEATER (REAR)NLEC1247S01Check the following.
1. Check resistance between terminals 2 and 3.
Resistance: 2.3 - 4.3Wat 25ÉC (77ÉF)
2. Check continuity.
Terminal No. Continuity
1 and 2, 3, 4
No
4 and 1, 2, 3
If NG, replace the heated oxygen sensor 2 (rear).
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 2 HEATER (REAR)QG18DE
Component Inspection
EC-438
Page 864 of 3051

SEF058X
JEF835Z
Component DescriptionNLEC1281The crankshaft position sensor (POS) is located on the right-rear
wall of the cylinder block in relation to the signal plate at the rear
end of the crankshaft.
The sensor consists of a permanent magnet, and hall IC.
When the engine is running, the high and low parts of the teeth
cause the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
The ECM receives the voltage signal and detects the fluctuation of
the engine revolution.
ECM Terminals and Reference ValueNLEC1282Specification 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 (AC Voltage)
85 RCrankshaft position
sensor (POS)[Engine is running]
+Warm-up condition
+Idle speed3-4V
SEF979W
[Engine is running]
+Engine speed is 2,000 rpm3-4V
SEF980W
CRANKSHAFT POSITION SENSOR (POS)QG18DE
Component Description
EC-439