NISSAN X-TRAIL 2001 Service Repair Manual

DTC P2138 APP SENSOR
EC-651
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EC
DTC P2138 APP SENSORPFP:18002
Component DescriptionEBS00NJY
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 ModeEBS00NJZ
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 ValueEBS00NK0
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 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
64 OR/LAccelerator pedal position
sensor 2 power supply[Ignition switch “ON”]Approximately 2.5V
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

EC-652
[QR25(WITHOUT EURO-OBD)]
DTC P2138 APP SENSOR
On Board Diagnosis Logic
EBS00NK1
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 ProcedureEBS00NK2
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-654, "
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-654, "
Diagnostic Procedure" .
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 TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138Accelerator pedal position
sensor circuit range/perfor-
mance problemRationally incorrect voltage is sent to ECM
compared with the signals from APP sensor
1 and APP sensor 2.
●Harness or connector
(The APP sensor 1 and 2 circuit is open
or shorted.)
●Accelerator pedal position sensor 1 and
2
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 P2138 APP SENSOR
EC-653
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EC
Wiring DiagramEBS00NK3
TBWA0325E

EC-654
[QR25(WITHOUT EURO-OBD)]
DTC P2138 APP SENSOR
Diagnostic Procedure
EBS00NK4
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.
PBIB0925E
PBIB0498E
APP sensor terminal Voltage (V)
4 Approximately 2.5
6 Approximately 5
PBIB0560E

DTC P2138 APP SENSOR
EC-655
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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-656, "
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-656
[QR25(WITHOUT EURO-OBD)]
DTC P2138 APP SENSOR
10. CHECK INTERMITTENT INCIDENT
Refer to EC-506, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00NK5
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 InstallationEBS00NK6
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 3200mV
76
(Accelerator pedal position
sensor 2)Fully released 0.15 - 0.48V
Fully depressed More than 1490mV
PBIB0561E

HO2S1 HEATER
EC-657
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EC
HO2S1 HEATERPFP:22690
DescriptionEBS00NC5
SYSTEM DESCRIPTION
The ECM performs ON/OFF duty control of the heated oxygen sensor 1 heater corresponding to the engine
speed and engine coolant temperature. The duty percent varies with engine coolant temperature when engine
is started.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeEBS00NC6
Specification data are reference values.
ECM Terminals and Reference ValueEBS00NC7
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.) Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 1
heater controlHeated oxygen sensor 1 heater
Engine coolant temperature sensorEngine coolant tempera-
ture
Engine speed rpm Heated oxygen sensor 1 heater
Above 3,600 OFF
Below 3,600 after warming up ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)
●Engine: After warming up
●Engine speed: Below 3,600 rpmON
●Engine speed: Above 3,600 rpm OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2P/LHeated oxygen sen-
sor 1 heater[Engine is running]
●Warm-up condition
●Engine speed is below 3,600 rpm.Approximately 7.0V
[Engine is running]
●Engine speed is above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
PBIB0519E

EC-658
[QR25(WITHOUT EURO-OBD)]
HO2S1 HEATER
Wiring Diagram
EBS00NC8
TBWA0075E

HO2S1 HEATER
EC-659
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Diagnostic ProcedureEBS00NC9
1.CHECK OVERALL FUNCTION CHECK
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch “OFF” and wait at least 10 seconds.
3. Turn ignition switch “ON”.
4. Set the tester probe between ECM terminals 2 (HO2S1 heater signal) and ground.
5. Start engine and let it idle.
6. Check the voltage under the following conditions.
Verify that the oscilloscope screen shows the signal wave as
shown below.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
OK or NG
OK >>INSPECTION END.
NG >> GO TO 2.
2.CHECK HO2S1 POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect heated oxygen sensor 1 harness connector.
3. Turn ignition switch “ON”.
4. Check voltage between HO2S1 terminal 4 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
Conditions Voltage
At idleApproximately 7.0V
Engine speed is above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB0673EPBIB0519E
PBIB0500E
Voltage: Battery voltage
PBIB0541E

EC-660
[QR25(WITHOUT EURO-OBD)]
HO2S1 HEATER
3. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E60, F36
●Fuse block (J/B) connector E103
●10A fuse
●Harness for open or short between heated oxygen sensor 1 and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK HO2S1 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 2 and HO2S1 terminal 1.
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 HEATED OXYGEN SENSOR 1 HEATER
Refer to EC-661, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 1.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-506, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.