2001 NISSAN X-TRAIL sensor

DTC P0121 APP SENSOR
EC-1223
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
On Board Diagnosis LogicEBS00N5F
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
ECM enters fail-safe mode when the malfunction is detected.
DTC Confirmation ProcedureEBS00N5G
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:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch “ON”.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-1226, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine and let it idle for 1 second.
76 B/WAccelerator pedal
position sensor 2[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.09 - 0.48V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 1.9V
86 LAccelerator pedal
position sensor 2
ground[Ignition switch “ON”]Approximately 0V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0121
0121Accelerator pedal posi-
tion sensor circuitA)An excessively low or high voltage from the
accelerator pedal position sensor 1 is sent to
ECM.
●Harness or connectors
(The accelerator pedal position
sensor 1 or 2 circuit is open or
shorted.)
●Electric throttle control actuator B)An excessively low or high voltage from the
accelerator pedal position sensor 2 is sent to
ECM.
C)A difference between signals from sensor 1 and
2 is out of the specified range.
Detected items Engine operating condition in fail-safe mode
Malfunction A The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the
idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor. Malfunction B
Malfunction C
SEF058Y

EC-1224
[QR20(WITHOUT EURO-OBD)]
DTC P0121 APP SENSOR
2. Turn ignition switch “OFF”, wait at least 10 seconds and then turn “ON”.
3. Perform “Diagnostic Test Mode II (Self-diagnostic results)” with ECM.
4. If DTC is detected, go to EC-1226, "
Diagnostic Procedure" .

DTC P0121 APP SENSOR
EC-1225
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Wiring DiagramEBS00N5H
TBWA0091E

EC-1226
[QR20(WITHOUT EURO-OBD)]
DTC P0121 APP SENSOR
Diagnostic Procedure
EBS00N5I
1. RETIGHTEN GROUND SCREWS
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2. CHECK APP SENSOR POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness
connector.
2. Turn ignition switch “ON”.
3. Check voltage between APP sensor terminals 4, 6 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 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.
PBIB0494E
PBIB0498E
APP sensor terminal Voltage (V)
4 Approximately 2.5
6 Approximately 5
PBIB0560E

DTC P0121 APP SENSOR
EC-1227
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
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

DTC P0134 HO2S1
EC-1229
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
DTC P0134 HO2S1PFP:22690
Component DescriptionEBS00N5L
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 ModeEBS00N5M
Specification data are reference values.
ECM Terminals and Reference ValueEBS00N5N
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-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
SEF646Y
PBIB0543E