2001 NISSAN X-TRAIL check engine

DTC P0121 APP SENSOR
EC-1227
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4.CHECK APP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between APP sensor terminal 1, 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 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors M61, F41
●Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 75 and APP sensor terminal 5, ECM terminal 76 and
APP sensor terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors M61, F41
●Harness for open or short between ECM and accelerator pedal position sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK APP SENSOR
Refer to EC-1228, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-1136, "
Accelerator Pedal Released Position Learning" .
>>INSPECTION END Continuity should exist.
Continuity should exist.

EC-1228
[QR20(WITHOUT EURO-OBD)]
DTC P0121 APP SENSOR
10. CHECK INTERMITTENT INCIDENT
Refer to EC-1192, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N5J
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform EC-1136, "
Accelerator Pedal Released Position Learning" .
3. Turn ignition switch “ON”.
4. Check voltage between ECM terminals 75 (APP sensor 1 sig-
nal), 76 (APP sensor 2 signal) and engine ground under the fol-
lowing conditions.
5. If NG, replace accelerator pedal assembly.
6. Perform EC-1136, "
Accelerator Pedal Released Position Learning" .
Remove and InstallationEBS00N5K
ACCELERATOR PEDAL
Refer to ACC-2, "ACCELERATOR CONTROL SYSTEM" .
Terminal Accelerator pedal Voltage
75
(Accelerator pedal position
sensor 1)Fully released 0.41 - 0.71V
Fully depressed More than 3.9V
76
(Accelerator pedal position
sensor 2)Fully released 0.09 - 0.48V
Fully depressed More than 1.9V
PBIB0561E

EC-1230
[QR20(WITHOUT EURO-OBD)]
DTC P0134 HO2S1
On Board Diagnosis Logic
EBS00N5O
Under the condition in which the heated oxygen sensor 1 signal is
not input, the ECM circuits will read a continuous approximately
0.3V. Therefore, for this diagnosis, the time that output voltage is
within 200 to 400 mV range is monitored, and the diagnosis checks
that this time is not inordinately long.
Overall Function CheckEBS00N5P
Use this procedure to check the overall function of the heated oxygen sensor 1 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “MANU TRIG” in “DATA MONITOR” mode with CON-
SULT-II, and select “HO2S1 (B1)”.
3. Hold engine speed at 2,000 rpm under no load.
4. Make sure that the indications do not remain in the range
between 0.2 to 0.4V.
5. If NG, go to EC-1232, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
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 the following with engine speed held at 2,000 rpm con-
stant under no load.
●The voltage does not remain in the range of 0.2 to 0.4V.
4. If NG, go to EC-1232, "
Diagnostic Procedure" .
SEF237U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0134
0134Heated oxygen sensor
1 circuit high no activity
detectedThe voltage from the sensor is constantly
approx. 0.3V.
●Harness or connectors
(The sensor circuit is open or shorted)
●Heated oxygen sensor 1
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PBIB0543E

EC-1232
[QR20(WITHOUT EURO-OBD)]
DTC P0134 HO2S1
Diagnostic Procedure
EBS00N5R
1. INSPECTION START
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2. CHECK HO2S1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect HO2S1 harness connector.
2. Check harness continuity between HO2S1 terminal 3 and
ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to power in harness or con-
nectors.
3. CHECK HO2S1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 92 and HO2S1 terminal 2.
Refer to Wiring Diagram.
3. Check harness continuity between ECM terminal 92 or HO2S1 terminal 2 and ground.
Refer to Wiring Diagram.
4. Also check harness for short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK HEATED OXYGEN SENSOR 1
Refer to EC-1233, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 1.
PBIB0494E
Continuity should exist.
PBIB0500E
Continuity should exist.
Continuity should not exist.

DTC P0134 HO2S1
EC-1233
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5.CHECK INTERMITTENT INCIDENT
Refer to EC-1192, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N5S
HEATED OXYGEN SENSOR 1
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “MANU TRIG” and adjust “TRIGGER POINT” to 100% in “DATA MONITOR” mode with CONSULT-
II.
3. Select “HO2S1 (B1)” and “HO2S1 MNTR (B1)”.
4. Hold engine speed at 2,000 rpm under no load during the follow-
ing steps.
5. Touch “RECORD” on CONSULT-II screen.
6. Check the following.
●“HO2S1 MNTR (B1)” in “DATA MONITOR” mode changes
from “RICH” to “LEAN” to “RICH” 5 times in 10 seconds.
5 times (cycles) are counted as shown at right.
●“HO2S1 (B1)” voltage goes above 0.6V at least once.
●“HO2S1 (B1)” voltage goes below 0.3V at least once.
●“HO2S1 (B1)” voltage never exceeds 1.0V.
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 system threads using Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 92 [HO2S1 (B1) signal] and engine ground.
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EC-1234
[QR20(WITHOUT EURO-OBD)]
DTC P0134 HO2S1
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.
●The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V
more than 5 times within 10 seconds.
●The maximum voltage is over 0.6V at least one time.
●The minimum voltage is below 0.3V at least one time.
●The voltage never exceeds 1.0V.
1 time: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V
2 times: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V → 0.6 - 1.0V
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 system threads using Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationEBS00N5T
HEATED OXYGEN SENSOR 1
Refer to EM-24, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
PBIB0543E

EC-1238
[QR20(WITHOUT EURO-OBD)]
DTC P0327, P0328 KS
Diagnostic Procedure
EBS00N5Z
1. CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check resistance between ECM terminal 82 and engine ground. Refer to Wiring Diagram.
NOTE:
It is necessary to use an ohmmeter which can measure more than 10 MΩ.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect knock sensor harness connector.
2. Check harness continuity between ECM terminal 82 and knock sensor terminal 1.
Refer to Wiring Diagram.
3. 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 KNOCK SENSOR
Refer to EC-1239, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace knock sensor.Resistance: Approximately 530 - 590kΩ [at 20°C (68°F)]
Continuity should exist.
PBIB0512E

DTC P0327, P0328 KS
EC-1239
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4.RETIGHTEN GROUND SCREWS
Loose and retighten engine ground screws.
>> GO TO 5.
5.CHECK INTERMITTENT INCIDENT
Refer to EC-1192, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N60
KNOCK SENSOR
Check resistance between knock sensor terminal 1 and ground.
NOTE:
It is necessary to use an ohmmeter which can measure more
than 10 MΩ.
CAUTION:
Do not use any knock sensors that have been dropped or phys-
ically damaged. Use only new ones.
Removal and InstallationEBS00N61
KNOCK SENSOR
Refer to EM-73, "CYLINDER BLOCK" .
PBIB0494E
Resistance: Approximately 530 - 590kΩ [at 20°C (68°F)]
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