2005 NISSAN X-TRAIL ignition

EC-148
[QR (WITH EURO-OBD)]
DTC P0037, P0038 HO2S2 HEATER

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.
Diagnostic ProcedureEBS010MY
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-132, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2PU/RHeated oxygen sensor 2
heater[Engine is running]

Engine speed is below 3,600 rpm after the follow-
ing conditions are met
–Warm-up condition
–Keeping the engine speed between 3,500 and
4,000 rpm for 1 minute and at idle for 1 minute
under no load0 - 1.0V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed is above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB2021E

DTC P0037, P0038 HO2S2 HEATER
EC-149
[QR (WITH EURO-OBD)]
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2. CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Turn ignition switch ON.
3. 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 open circuit or short to ground or short or 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 2 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 open circuit or short to ground or short to power in harness or connectors.
5. CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-150, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 2.
PBIB0500E
Voltage: Battery voltage
PBIB0541E
Continuity should exist.

DTC P0102, P0103 MAF SENSOR
EC-151
[QR (WITH EURO-OBD)]
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DTC P0102, P0103 MAF SENSORPFP:22680
Component DescriptionEBS010N1
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor controls the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeEBS010N2
Specification data are reference values.
On Board Diagnosis LogicEBS010N3
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
DTC Confirmation ProcedureEBS010N4
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR DTC P0102
With CONSULT-II
1. Turn ignition switch ON.
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-120, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Air conditioner switch: OFF

Shift lever: P or N (A/T), Neutral
(M/T)

No loadIdle 10% - 35%
2,500 rpm 10% - 35%
MASS AIRFLOW

Engine: After warming up

Air conditioner switch: OFF

Shift lever: P or N (A/T), Neutral
(M/T)

No loadIdle 1.0 - 4.0 g·m/s
2,500 rpm 4.0 - 10.0 g·m/s
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0102
0102Mass air flow sensor circuit
low inputAn excessively low voltage from the sensor
is sent to ECM when engine is running.

Harness or connectors
(The sensor circuit is open or shorted.)

Intake air leaks

Mass air flow sensor
P0103
0103Mass air flow sensor circuit
high inputAn excessively high voltage from the sensor
is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Mass air flow sensor
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.

EC-152
[QR (WITH EURO-OBD)]
DTC P0102, P0103 MAF SENSOR

2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and wait at least 5 seconds.
4. If DTC is detected, go to EC-154, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR DTC P0103
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If DTC is detected, go to EC-154, "
Diagnostic Procedure" .
If DTC is not detected, go to next step.
5. Start engine and wait at least 5 seconds.
6. If DTC is detected, go to EC-154, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
SEF058Y
SEF058Y

EC-154
[QR (WITH EURO-OBD)]
DTC P0102, P0103 MAF SENSOR

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.
Diagnostic ProcedureEBS010N6
1. INSPECTION START
Which malfunction (P0102 or P0103) is duplicated?
P0102 or P0103
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2. CHECK INTAKE SYSTEM
Check the following for connection.

Air duct

Va c u u m h o s e s

Intake air passage between air duct and intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
50 OR Mass air flow sensor[Ignition switch: ON]Approximately 0.4V
[Engine is running]

Warm-up condition

Idle speed0.7 - 1.1V (QR20DE)
0.8 - 1.2V (QR25DE)
[Engine is running]

Warm-up condition

Engine is revving from idle to about 4,000 rpm0.7 - 1.1 to Approximately 4.0V
(QR20DE)
0.8 - 1.2 to Approximately 4.0V
(QR25DE)
(Check for liner voltage rise in
response to engine being
increased to about 4,000 rpm.)
67 B/PSensor ground
(Mass air flow sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V

DTC P0102, P0103 MAF SENSOR
EC-155
[QR (WITH EURO-OBD)]
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3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-132, "
Ground Inspection" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace ground connections.
PBIB2021E

EC-156
[QR (WITH EURO-OBD)]
DTC P0102, P0103 MAF SENSOR

4. CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect MAF sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between MAF sensor terminals 2 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors F41, M61

Harness for open or short between mass air flow sensor and ECM

Harness for open or short between mass air flow sensor and ECM relay
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 and ECM terminal 67.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB0495E
Voltage: Battery voltage
PBIB1168E
Continuity should exist.

DTC P0102, P0103 MAF SENSOR
EC-157
[QR (WITH EURO-OBD)]
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7. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 50.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK MASS AIR FLOW SENSOR
Refer to EC-157, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Replace mass air flow sensor.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-124, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS01FF1
MASS AIR FLOW SENSOR
With CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-II and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the follow-
ing conditions.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
5. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 to 4 again.
If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor harness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.Continuity should exist.
Condition Voltage V
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating
temperature.)0.7 - 1.1V (QR20DE)
0.8 - 1.2V (QR25DE)
Idle to about 4,000 rpm0.7 - 1.1 to 2.4 (QR20DE)*
0.8 - 1.2 to 2.4 (QR25DE)*
SEF178Y