NISSAN X-TRAIL 2001 Service Repair Manual

HO2S1 HEATER
EC-1311
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Component InspectionEBS00N8N
HEATED OXYGEN SENSOR 1 HEATER
1. Check resistance between HO2S1 terminals as follows.
2. If NG, replace heated oxygen sensor 1.
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.
Removal and InstallationEBS00N8O
HEATED OXYGEN SENSOR 1
Refer to EM-24, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
Terminal No. Resistance
1 and 4 2.3 - 4.3 Ω at 25°C (77°F)
2 and 3, 4
∞Ω
(Continuity should not exist)
3 and 1, 2, 4
PBIB0542E

EC-1312
[QR20(WITHOUT EURO-OBD)]
HO2S2 HEATER
HO2S2 HEATER
PFP:226A0
DescriptionEBS00N8P
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeEBS00N8Q
Specification data are reference values.
ECM Terminals and Reference ValueEBS00N8R
Specification data are reference values and are measured between each terminal and body 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.
Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Engine speedHeated oxygen sensor 2
heater controlHeated oxygen sensor 2 heater
Crankshaft position sensor (POS)
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,800 OFF
Below 3,800 ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
●Engine speed: Below 3,800 rpm [After driving for 2 minutes at a speed
of 70 km/h (43 MPH) or more]ON
●Engine speed: Above 3,800 rpm OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
4PU/RHeated oxygen sen-
sor 2 heater[Engine is running]
●Engine speed is below 3,800 rpm.
●After driving for 2 minutes at a speed of 70 km/h
(43 MPH) or more.0 - 1.0V
[Ignition switch “ON”]
●Engine stopped
[Engine is running]
●Engine speed is above 3,800 rpm.BATTERY VOLTAGE
(11 - 14V)

HO2S2 HEATER
EC-1313
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Wiring DiagramEBS00N8S
TBWA0077E

EC-1314
[QR20(WITHOUT EURO-OBD)]
HO2S2 HEATER
Diagnostic Procedure
EBS00N8T
1. CHECK OVERALL FUNCTION CHECK
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 terminal 4 (HO2S2 heater signal) and ground.
4. Check the voltage under the following conditions.
OK or NG
OK >>INSPECTION END.
NG >> GO TO 2.
2. CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Turn ignition switch “ON”.
4. Check voltage between HO2S2 terminal 4 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E60, F36
●Fuse block (J/B) connector E103
●10A fuse
●Harness for open or short between heated oxygen sensor 2 and fuse
>> Repair harness or connectors.
Conditions Voltage
At idle 0 - 1V
Engine speed is above
3,800 rpmBattery voltage
PBIB0672E
PBIB0500E
Voltage: Battery voltage
PBIB0541E

HO2S2 HEATER
EC-1315
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
4.CHECK HO2S2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 4 and HO2S2 terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connectors.
5.CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-1315, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 2.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-1192, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N8U
HEATED OXYGEN SENSOR 2 HEATER
1. Check resistance between HO2S2 terminals as follows.
2. If NG, replace heated oxygen sensor 2.
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 sur-
face such as a concrete floor; use a new one.
●Before installing new oxygen sensor, clean exhaust system
threads using Oxygen Sensor Thread Cleaner tool J-43897-
18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationEBS00N8V
HEATED OXYGEN SENSOR 2
Refer to EX-2, "EXHAUST SYSTEM" . Continuity should exist.
Terminal No. Resistance
1 and 4 2.3 - 4.3 Ω at 25°C (77°F)
2 and 1, 3, 4
∞Ω
(Continuity should not exist)
3 and 1, 2, 4
PBIB0542E

EC-1316
[QR20(WITHOUT EURO-OBD)]
IAT SENSOR
IAT SENSOR
PFP:22630
Component DescriptionEBS00N8W
The intake air temperature sensor is built into mass air flow sensor.
The sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: These data are reference values and are measured between ECM terminal 84
(Intake air temperature sensor) and body ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
SEC266C
Intake air
temperature°C (°F)Vo lta g e * V R e s i s ta n c e kΩ
25 (77) 3.32 1.9 - 2.1
80 (176) 1.23 0.31 - 0.37
SEF012P

IAT SENSOR
EC-1317
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Wiring DiagramEBS00N8X
TBWA0073E

EC-1318
[QR20(WITHOUT EURO-OBD)]
IAT SENSOR
Diagnostic Procedure
EBS00N8Y
1. CHECK OVERALL FUNCTION
1. Turn ignition switch "ON".
2. Check voltage between ECM terminal 84 and ground with CON-
SULT-II or tester.
OK or NG
OK >>INSPECTION END.
NG >> GO TO 2.
2. CHECK INTAKE AIR TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect mass air flow sensor (intake air temperature sensor
is built-into) harness connector.
3. Turn ignition switch “ON”.
4. Check voltage between MAF sensor terminal 5 and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connectors.
3. CHECK INTAKE AIR TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between mass air flow sensor terminal 3 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connectors.Voltage: 0.04 - 4.84V
PBIB0674E
PBIB0495E
Voltage: Approximately 5V
PBIB0066E
Continuity should exist.

IAT SENSOR
EC-1319
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
4.CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-1319, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace mass air flow sensor (with intake air temperature sensor).
5.CHECK INTERMITTENT INCIDENT
Refer to EC-1192, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N8Z
INTAKE AIR TEMPERATURE SENSOR
1. Check resistance between intake air temperature sensor termi-
nals 3 and 5 under the following conditions.
2. If NG, replace mass air flow sensor (with intake air temperature
sensor).
Removal and InstallationEBS00N90
MASS AIR FLOW SENSOR
Refer to EM-14, "AIR CLEANER AND AIR DUCT" .
Intake air temperature °C (°F) Resistance kΩ
25 (77) 1.9 - 2.1
SEC266C
SEF012P

EC-1320
[QR20(WITHOUT EURO-OBD)]
HO2S1
HO2S1
PFP:22690
Component DescriptionEBS00N91
The heated oxygen sensor 1 is placed into the exhaust manifold. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 has a closed-end tube
made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions. The
heated oxygen sensor 1 signal is sent to the ECM. The ECM adjusts
the injection pulse duration to achieve the ideal air-fuel ratio. The
ideal air-fuel ratio occurs near the radical change from 1V to 0V.
CONSULT-II Reference Value in Data Monitor ModeEBS00N92
Specification data are reference values.
ECM Terminals and Reference ValueEBS00N93
Specification 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.
SEF463R
SEF288D
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
●Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S1 MNTR (B1)
●Engine: After warming upMaintaining engine speed at 2,000
rpmLEAN ←→ RICH
Changes more than 5 times dur-
ing 10 seconds.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
92 G/WHeated oxygen sen-
sor 1[Engine is running]
●Warm-up condition
●Engine speed is 2,000 rpm.0 - Approximately 1.0V (Periodi-
cally change)