NISSAN X-TRAIL 2001 Service Repair Manual

DTC P2122, P2123 APP SENSOR
EC-631
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DTC P2122, P2123 APP SENSORPFP:18002
Component DescriptionEBS00NJ7
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeEBS00NJ8
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM. Thus, it differs from ECM terminals voltage signal.
ECM Terminals and Reference ValueEBS00NJ9
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.
PBIB0146E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN1
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.41 - 0.72V
Accelerator pedal: Fully depressed 3.2 - 4.9V
ACCEL SEN*
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.15 - 0.98V
Accelerator pedal: Fully depressed 2.98 - 4.9V
CLSD THL POS
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
58 B Sensors' ground[Engine is running]
●Warm-up condition
●Idle speedApproximately 0V
65 R Sensor's power supply[Ignition switch “ON”]Approximately 5V
75 R/LAccelerator pedal position
sensor 1[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.41 - 0.72V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 3.2V
76 W/BAccelerator pedal position
sensor 2[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.15 - 0.48V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 1.49V

EC-632
[QR25(WITHOUT EURO-OBD)]
DTC P2122, P2123 APP SENSOR
On Board Diagnosis Logic
EBS00NJA
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 ProcedureEBS00NJB
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-634, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine and let it idle for 1 second.
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-634, "
Diagnostic Procedure" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2122
2122Accelerator pedal position
sensor 1 circuit low inputAn excessively low voltage from the APP
sensor 1 is sent to ECM.
●Harness or connectors
(The APP sensor 1 circuit is open or
shorted.)
●Accelerator pedal position sensor
(Accelerator pedal position sensor 1) P2123
2123Accelerator pedal position
sensor 1 circuit high inputAn excessively high voltage from the APP
sensor 1 is sent to ECM.
Engine operating condition in fail-safe mode
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.
SEF058Y

DTC P2122, P2123 APP SENSOR
EC-633
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Wiring DiagramEBS00NJC
TBWA0326E

EC-634
[QR25(WITHOUT EURO-OBD)]
DTC P2122, P2123 APP SENSOR
Diagnostic Procedure
EBS00NJD
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 terminal 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.
PBIB0925E
PBIB0498E
Voltage: Approximately 5V
PBIB0914E

DTC P2122, P2123 APP SENSOR
EC-635
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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 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.
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-636, "
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-449, "
Accelerator Pedal Released Position Learning" .
>>INSPECTION END Continuity should exist.
Continuity should exist.

EC-636
[QR25(WITHOUT EURO-OBD)]
DTC P2122, P2123 APP SENSOR
10. CHECK INTERMITTENT INCIDENT
Refer to EC-506, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00NJE
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform EC-449, "
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 and go to next step.
6. Perform EC-449, "
Accelerator Pedal Released Position Learning" .
7. Perform EC-449, "
Throttle Valve Closed Position Learning" .
8. Perform EC-450, "
Idle Air Volume Learning" .
Remove and InstallationEBS00NJF
ACCELERATOR PEDAL
Refer to ACC-2, "ACCELERATOR CONTROL SYSTEM" .
Terminal Accelerator pedal Voltage
75
(Accelerator pedal position
sensor 1)Fully released 0.41 - 0.72V
Fully depressed More than 3.2V
76
(Accelerator pedal position
sensor 2)Fully released 0.15 - 0.48V
Fully depressed More than 1.49V
PBIB0561E

DTC P2127, P2128 APP SENSOR
EC-637
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EC
DTC P2127, P2128 APP SENSORPFP:18002
Component DescriptionEBS00NJG
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeEBS00NJH
Specification data are reference values.
*:Accelerator pedal position sensor 2 signal is converted by ECM. Thus, it differs from ECM terminal voltage.
ECM Terminals and Reference ValueEBS00NJI
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.
PBIB0146E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN1
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.41 - 0.72V
Accelerator pedal: Fully depressed 3.2 - 4.9V
ACCEL SEN2*
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.15 - 0.98V
Accelerator pedal: Fully depressed More than 2.98 - 4.9V
CLSD THL POS
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
64 OR/LAccelerator pedal position
sensor 2 power supply[Ignition switch “ON”]Approximately 2.5V
75 R/LAccelerator pedal position
sensor 1[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.41 - 0.72V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 3.2V
76 W/BAccelerator pedal position
sensor 2[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.15 - 0.48V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 1.49V
86 LAccelerator pedal position
sensor 2 ground[Ignition switch “ON”]Approximately 0V

EC-638
[QR25(WITHOUT EURO-OBD)]
DTC P2127, P2128 APP SENSOR
On Board Diagnosis Logic
EBS00NJJ
These self-diagnoses have the one trip detection logic.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2127
2127Accelerator pedal position
sensor 2 circuit low inputAn excessively low voltage from the APP
sensor 2 is sent to ECM.
●Harness or connectors
(The APP sensor 2 circuit is open or
shorted.)
●Accelerator pedal position sensor
(Accelerator pedal position sensor 2) P2128
2128Accelerator pedal position
sensor 2 circuit high inputAn excessively high voltage from the APP
sensor 2 is sent to ECM.

DTC P2127, P2128 APP SENSOR
EC-639
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EC
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
DTC Confirmation ProcedureEBS00NJK
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-641, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine and let it idle for 1 second.
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 1st trip DTC is detected, go to EC-641, "
Diagnostic Procedure" .
Engine operating condition in fail-safe mode
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.
SEF058Y

EC-640
[QR25(WITHOUT EURO-OBD)]
DTC P2127, P2128 APP SENSOR
Wiring Diagram
EBS00NJL
TBWA0331E