2001 NISSAN X-TRAIL sensor

DTC P0550 PSP SENSOR
EC-257
[QR25(WITH EURO-OBD)]
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Wiring DiagramEBS00M6J
TBWA0150E

EC-258
[QR25(WITH EURO-OBD)]
DTC P0550 PSP SENSOR
Diagnostic Procedure
EBS00M6K
1. RETIGHTEN GROUND SCREWS
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2. CHECK PSP SENSOR POWER SUPPLY CIRCUIT
1. Disconnect PSP sensor harness connector.
2. Turn ignition switch “ON”.
3. Check voltage between PSP sensor terminal 3 and ground with
CONSULT-II or tester.
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 PSP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between PSP sensor terminal 1 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 ground or short to power harness or connectors.
PBIB0494E
PBIB0502E
Voltage: Approximately 5V
SEF509Y
Continuity should exist.

DTC P0550 PSP SENSOR
EC-259
[QR25(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-259, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace PSP sensor.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00M6L
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

EC-276
[QR25(WITH EURO-OBD)]
DTC P1121 ELECTRIC THROTTLE CONTROL ACTUATOR
DTC P1121 ELECTRIC THROTTLE CONTROL ACTUATOR
PFP:16119
DescriptionEBS00M79
Electric Throttle Control Actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The throttle position sensor detects the throttle valve position, and the opening and closing speed of the throt-
tle valve and feeds the voltage signals to the ECM. The ECM judges the current opening angle of the throttle
valve from these signals and the ECM controls the throttle control motor to make the throttle valve opening
angle properly in response to driving condition.
On Board Diagnosis LogicEBS00M7A
FAIL-SAFE MODE
When the malfunction A or B is detected in the two consecutive trips, the ECM enters fail-safe mode and the
MI lights up.
When the malfunction C is detected even in the 1st trip, the ECM enters fail-safe mode and the MI lights up.
DTC Confirmation ProcedureEBS00M7B
NOTE:
●Perform “PROCEDURE FOR MALFUNCTION A AND B” first. If the 1st trip DTC cannot be con-
firmed, perform “PROCEDURE FOR MALFUNCTION C”.
If there is no malfunction on “PROCEDURE FOR MALFUNCTION A AND B”, perform “PROCE-
DURE FOR MALFUNCTION C”.
●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 MALFUNCTION A AND B
With CONSULT-II
1. Turn ignition witch “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. Turn ignition switch “OFF”, wait at least 10 seconds, and then
turn “ON”.
5. If DTC is detected, go to EC-277, "
Diagnostic Procedure" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1121
11 2 1Electric throttle control
actuatorA)Electric throttle control actuator does not func-
tion properly due to the return spring malfunc-
tion.
●Electric throttle control actuator B)Throttle valve opening angle in fail-safe mode is
not in specified range.
C)ECM detects the throttle valve is stuck open.
This self-diagnosis has the one trip detec-
tion logic.
Detected items Engine operating condition in fail-safe mode
Malfunction AThe ECM controls the electric throttle actuator by regulating the throttle opening around the idle position.
The engine speed will not rise more than 2,000 rpm.
Malfunction B ECM controls the electric throttle control actuator by regulating the throttle opening to 20 degrees or less.
Malfunction CWhile the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the engine stalls.
The engine can restart in “N” or “P” position, and engine speed will not exceed 1,000 rpm or more.
SEF058Y

EC-278
[QR25(WITH EURO-OBD)]
DTC P1122 ELECTRIC THROTTLE CONTROL FUNCTION
DTC P1122 ELECTRIC THROTTLE CONTROL FUNCTION
PFP:16119
DescriptionEBS00NBU
NOTE:
If DTC P1122 is displayed with DTC P1121 or 1126, first perform the trouble diagnosis for DTC P1121 or
P1126. Refer to EC-276
or EC-285 .
Electric Throttle Control Actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.
CONSULT-II Reference Value in Data Monitor ModeEBS00NBV
Specification data are reference values.
ECM Terminals and Reference ValueEBS00NBW
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) MONITOR ITEM CONDITION SPECIFICATION
THRTL RELAY
●Ignition switch: ON ON
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MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
11 2 W / RThrottle control motor
relay[Ignition switch “OFF”]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]0 - 1.0V
11 3 W / BThrottle control motor
relay power supply[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
11 4 RThrottle control motor
(Open)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is depressing0 - 14V
11 5 B / YThrottle control motor
ground[Engine is running]
●Idle speedApproximately 0V
11 6 GThrottle control motor
(Close)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is releasing0 - 14V
PBIB0533E
PBIB0534E

EC-290
[QR25(WITH EURO-OBD)]
DTC P1128 THROTTLE CONTROL MOTOR
DTC P1128 THROTTLE CONTROL MOTOR
PFP:16119
Component DescriptionEBS00MPV
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.
ECM Terminals and Reference ValueEBS00MPW
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
On Board Diagnosis LogicEBS00MPX
This self-diagnosis has 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 ProcedureEBS00MPY
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
11 4 RThrottle control motor
(Open)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is depressing0 - 14V
11 5 B / YThrottle control motor
ground[Engine is running]
●Idle speedApproximately 0V
11 6 GThrottle control motor
(Close)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is releasing0 - 14V
PBIB0533E
PBIB0534E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1128
11 2 8Throttle control motor
circuit shortECM detects short in both circuits between
ECM and throttle control motor.
●Harness or connectors
(Throttle control motor circuit is shorted.)
●Electric throttle control actuator
(Throttle control motor)
Engine operating condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return
spring.

DTC P1143 HO2S1
EC-295
[QR25(WITH EURO-OBD)]
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DTC P1143 HO2S1PFP:22690
Component DescriptionEBS00M7X
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 ModeEBS00M7Y
Specification data are reference values.
ECM Terminals and Reference ValueEBS00M7Z
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)

EC-296
[QR25(WITH EURO-OBD)]
DTC P1143 HO2S1
On Board Diagnosis Logic
EBS00M80
To judge the malfunction, the output from the heated oxygen sensor
1 is monitored to determine whether the “rich” output is sufficiently
high and whether the “lean” output is sufficiently low. When both the
outputs are shifting to the lean side, the malfunction will be detected.
DTC Confirmation ProcedureEBS00M81
CAUTION:
Always drive vehicle at a safe speed.
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.
TESTING CONDITION:
●Always perform at a temperature above −10°C (14°F).
●Before performing following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine and wait at least 10 seconds.
3. Turn ignition switch “ON” and select “HO2S1 (B1) P1143” of “HO2S1” in “DTC WORK SUPPORT” mode
with CONSULT-II.
4. Touch “START”.
5. Start engine and let it idle for at least 3 minutes.
NOTE:
Never raise engine speed above 3,600 rpm after this step. If
the engine speed limit is exceeded, return to step 5.
SEF300U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1143
11 4 3Heated oxygen sensor
1 lean shift monitoringThe maximum and minimum voltage from the
sensor are not reached to the specified volt-
ages.
●Heated oxygen sensor 1
●Heated oxygen sensor 1 heater
●Fuel pressure
●Injectors
●Intake air leaks
PBIB0546E