NISSAN X-TRAIL 2001 Service Repair Manual

HO2S1 HEATER
EC-661
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Component InspectionEBS00NCA
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 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 InstallationEBS00NCB
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-662
[QR25(WITHOUT EURO-OBD)]
HO2S2 HEATER
HO2S2 HEATER
PFP:226A0
DescriptionEBS00NCC
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 ModeEBS00NCD
Specification data are reference values.
ECM Terminals and Reference ValueEBS00NCE
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.
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 3,600 OFF
●Below 3,600 rpm after the following conditions are met.
●Engine: After warming up
●Keeping the engine speed between 3,500 and 4,000 rpm for
one minute and at idle for one minute under no loadON
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
●Engine speed: Below 3,600 rpm after the following conditions are met.
●Engine: After warming up
●Keeping the engine speed between 3,500 and 4,000 rpm for one minute
and at idle for one minute under on loadON
●Engine speed: Above 3,600 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 3,600 rpm after the follow-
ing conditions are met.
●Engine: after warming up
●Keeping the engine speed between 3,500 and
4,000 rpm for one minute and at idle for one
minute under no load.0 - 1.0V
[Ignition switch “ON”]
●Engine stopped
[Engine is running]
●Engine speed is above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)

HO2S2 HEATER
EC-663
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Wiring DiagramEBS00NCF
TBWA0077E

EC-664
[QR25(WITHOUT EURO-OBD)]
HO2S2 HEATER
Diagnostic Procedure
EBS00NCG
1. CHECK OVERALL FUNCTION CHECK
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch “OFF” and wait at least 10 seconds.
3. Start engine and keep the engine speed at between 3,500 to 4,000 rpm for at least one minute under no
load.
4. Let engine idle for one minute.
5. Set voltmeter probes between ECM terminal 95 (HO2S2 signal) and ground.
6. Check the voltage while revving engine up to 4,000 rpm under
no load at least 10 times. (Depress and release the accelerator
pedal as quickly as possible.)
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.The voltage does not remain in the range of 0.2 to 0.4V
PBIB0675E
PBIB0500E
Voltage: Battery voltage
PBIB0541E

HO2S2 HEATER
EC-665
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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 open circuit or short to ground or short to power in harness or connectors.
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-666, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 2.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-506, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.

EC-666
[QR25(WITHOUT EURO-OBD)]
HO2S2 HEATER
Component Inspection
EBS00NCH
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 InstallationEBS00NCI
HEATED OXYGEN SENSOR 2
Refer to EX-2, "EXHAUST SYSTEM" .
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

IAT SENSOR
EC-667
[QR25(WITHOUT EURO-OBD)]
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EC
IAT SENSORPFP:22630
Component DescriptionEBS00NCJ
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 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)Voltage* V Resistance kΩ
25 (77) 3.32 1.9 - 2.1
80 (176) 1.23 0.31 - 0.37
SEF012P

EC-668
[QR25(WITHOUT EURO-OBD)]
IAT SENSOR
Wiring Diagram
EBS00NCK
TBWA0073E

IAT SENSOR
EC-669
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Diagnostic ProcedureEBS00NCL
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 open circuit or short to ground or short to power
in 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 power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to power in harness or connectors. Voltage: 0.04 - 4.84V
PBIB0674E
PBIB0495E
Voltage: Approximately 5V
PBIB0066E
Continuity should exist.

EC-670
[QR25(WITHOUT EURO-OBD)]
IAT SENSOR
4. CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-670, "
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-506, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00NCM
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 InstallationEBS00NCN
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