2001 NISSAN X-TRAIL check engine

DTC P0550 PSP SENSOR
EC-987
[QR20(WITH EURO-OBD)]
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4.CHECK PSP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 67 and PSP sensor terminal 2.
3. 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 PSP SENSOR
Refer to EC-987, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace PSP sensor.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-847, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00MYG
POWER STEERING PRESSURE SENSOR
1. Reconnect all harness connectors disconnected.
2. Start engine and let it idle.
3. Check voltage between ECM terminal 67 and ground under the
following conditions.Continuity should exist.
Condition Voltage
Steering wheel is being turned fully. Approximately 3.6V
Steering wheel is not being turned. Approximately 0.6V
PBIB0570E

DTC P0650 MI
EC-991
[QR20(WITH EURO-OBD)]
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DTC P0650 MIPFP:24810
Component DescriptionEBS00MYL
Malfunction Indicator (MI) is located on the instrument panel. When the ignition switch is turned ON without
engine running, MI will light up. This is a bulb check. When the engine is started, MI should go off. If MI
remains on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnosis LogicEBS00MYM
The MI will not light up for this diagnosis.
FAIL-SAFE MODE
ECM enters fail-safe mode when both DTC P0650 and another DTC, which calls for MI to light up, are
detected at the same time.
DTC Confirmation ProcedureEBS00MYN
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.
WITH CONSULT-II
1. Turn ignition switch “ON” and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If 1st trip DTC is detected, go to EC-993, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0650
0650Malfunction indicator
(MI) control circuit
●An excessively high voltage is sent to ECM
through the MI circuit under the condition
that calls for MI light up.
●An excessively low voltage is sent to ECM
through the MI circuit under the condition
that calls for MI not to light up.
●Harness or connectors
(MI circuit is open or shorted.)
●MI
Detected items Engine operating condition in fail-safe mode
MI circuit Engine speed will not rise more than 2,500 rpm due to the fuel cut
SEF058Y

EC-1002
[QR20(WITH EURO-OBD)]
DTC P1102 MAF SENSOR
Diagnostic Procedure
EBS00MZ1
1. RETIGHTEN GROUND SCREWS
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2. 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, 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 for open or short between ECM relay and mass air flow sensor
●Harness for open or short between mass air flow sensor and ECM
>> Repair harness or connectors.
PBIB0494E
PBIB0495E
Terminal Voltage
2 Approximately 5V
4 Battery voltage
PBIB0076E

DTC P1102 MAF SENSOR
EC-1003
[QR20(WITH EURO-OBD)]
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4.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 80.
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 MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 1 and ECM terminal 72.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK MASS AIR FLOW SENSOR
Refer to EC-1003, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace mass air flow sensor.
7.CHECK INTERMITTENT INCIDENT
Refer to EC-847, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00MZ2
MASS AIR FLOW SENSOR
1. Reconnect harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 72 (Mass air flow sensor
signal) and ground.
*: Check for liner voltage rise in response to engine being increased to about
4,000 rpm.
4. If the voltage is out of specification, proceed the following.
●Turn ignition switch “OFF”.
●Disconnect mass air flow sensor harness connector and reconnect it again. Continuity should exist.
Continuity should exist.
Condition Voltage V
Ignition switch “ON” (Engine stopped.) Approx. 1.0
Idle (Engine is warmed-up to normal
operating temperature.)1.1 - 1.5
2,500 rpm (Engine is warmed-up to
normal operating temperature.)1.6 - 2.0
Idle to about 4,000 rpm* 1.5 - 2.0 to Approx. 4.0
PBIB0537E

DTC P1121 ELECTRIC THROTTLE CONTROL ACTUATOR
EC-1011
[QR20(WITH EURO-OBD)]
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With GST
Follow the procedure “WITH CONSULT-II” above.
PROCEDURE FOR MALFUNCTION C
With CONSULT-II
1. Turn ignition switch “ON” and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Shift selector lever to “D” position (A/T), “1st” position (M/T) and
wait at least 2 seconds.
4. Shift selector lever to “N” or “P” position.
5. Start engine and let it idle for 3 seconds.
6. If 1st trip DTC is detected, go to EC-1011, "
Diagnostic Proce-
dure" .
With GST
Follow the procedure “With CONSULT-II” above.
Diagnostic ProcedureEBS00MZG
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Remove the intake air duct.
2. Check if a foreign matter is caught between the throttle valve
and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle
control actuator inside.
2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-772, "
Throttle Valve Closed Position Learning" .
3. Perform EC-772, "
Idle Air Volume Learning" .
>>INSPECTION END
SEF058Y
PBIB0518E

DTC P1122 ELECTRIC THROTTLE CONTROL FUNCTION
EC-1015
[QR20(WITH EURO-OBD)]
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Diagnostic ProcedureEBS00MZM
1.RETIGHTEN GROUND SCREWS
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2.CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Disconnect electric throttle control actuator harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
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 THROTTLE CONTROL MOTOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between ECM terminal 115 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.
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Electric throttle control
actuator terminalECM terminal Continuity
6114 Should exist
116 Should not exist
3114 Should not exist
116 Should exist
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Continuity should exist.

DTC P1143 HO2S1
EC-1025
[QR20(WITH EURO-OBD)]
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6. When the following conditions are met, “TESTING” will be dis-
played on the CONSULT-II screen. Maintain the conditions con-
tinuously until “TESTING” changes to “COMPLETED”. (It will
take approximately 50 seconds or more.)
If “TESTING” is not displayed after 5 minutes, retry from
step 2.
7. Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”. If “NG” is displayed, refer to EC-1025, "
Diagnostic
Procedure" .
Overall Function CheckEBS00N01
Use this procedure to check the overall function of the heated oxygen sensor 1 circuit. During this check, a
DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 92 (HO2S1 signal) and engine ground.
3. Check one of the following with engine speed held at 2,000 rpm
constant under no load.
–The maximum voltage is over 0.6V at least one time.
–The minimum voltage is over 0.1V at least one time.
4. If NG, go to EC-1025, "
Diagnostic Procedure" .
Diagnostic ProcedureEBS00N02
1.RETIGHTEN GROUND SCREWS
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
ENG SPEED 1,400 - 3,200 rpm
Vehicle speed Less than 100 km/h (62 MPH)
B/FUEL SCHDL 2.9 - 14.5 msec
Selector lever Suitable position
PBIB0547E
SEC769C
PBIB0543E
PBIB0494E

EC-1026
[QR20(WITH EURO-OBD)]
DTC P1143 HO2S1
2. RETIGHTEN HEATED OXYGEN SENSOR 1
Loosen and retighten heated oxygen sensor 1.
>> GO TO 3.
3. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch “OFF”.
3. Disconnect mass air flow sensor harness connector, and restart
and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-788, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171. Refer to EC-934 .
No >> GO TO 4.
4. CHECK HEATED OXYGEN SENSOR 1 HEATER
Refer to EC-864, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace heated oxygen sensor 1.Tightening torque: 40 - 50 N·m (4.1 - 5.1 kg-m, 30 - 37 ft-lb)
PBIB0499E
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