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EC-536Revision: June 2006
DTC P2138 APP SENSOR
2007 Versa
Diagnostic ProcedureUBS00QNM
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor (1) harness
connector.
2. Turn ignition switch ON.
3. Check voltage between APP sensor terminal 4 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.
:Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15
BBIA0698E
BBIA0705E
Voltage: Approximately 5V
PBIA9606J
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DTC P2138 APP SENSOR
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3. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ON.
2. Check voltage between APP sensor terminal 5 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
4. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between APP sensor terminal 5 and ECM terminal 102.
Refer to Wiring Diagram.
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 APP SENSOR 2 POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 6.
NG >> Repair short to ground or short to power in harness or connectors.
6. CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-326, "Component Inspection" .)
Refrigerant pressure sensor (Refer to MTC-24, "TROUBLE DIAGNOSIS" .)
OK or NG
OK >> GO TO 11.
NG >> Replace malfunctioning component.Voltage: Approximately 5V
PBIA9607J
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
74 Refrigerant pressure sensor terminal 3EC-587, "
Wiring Diagram"
75 Crankshaft position sensor (POS) terminal 1EC-321, "Wiring Diagram"
102 APP sensor terminal 5EC-534, "Wiring Diagram"
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EC-538Revision: June 2006
DTC P2138 APP SENSOR
2007 Versa
7. CHECK APP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between the following;
ECM terminal 111 and APP sensor terminal 2,
ECM terminal 104 and APP sensor terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between the following;
ECM terminal 110 and APP sensor terminal 3,
ECM terminal 103 and APP sensor terminal 6.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK APP SENSOR
Refer to EC-539, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-78, "
Throttle Valve Closed Position Learning" .
4. Perform EC-78, "
Idle Air Volume Learning" .
>>INSPECTION END
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-143, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
Continuity should exist.
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DTC P2138 APP SENSOR
EC-539
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Component InspectionUBS00QNN
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 110 (APP sensor 1 sig-
nal), 103 (APP sensor 2 signal) and ground under the following
conditions.
4. If NG, replace accelerator pedal assembly and go to next step.
5. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-78, "
Throttle Valve Closed Position Learning" .
7. Perform EC-78, "
Idle Air Volume Learning" .
Removal and InstallationUBS00QNO
ACCELERATOR PEDAL
Refer to ACC-3, "ACCELERATOR CONTROL SYSTEM" .
Terminal Accelerator pedal Voltage
11 0
(Accelerator pedal position
sensor 1)Fully released 0.6 - 0.9V
Fully depressed 3.9 - 4.7V
103
(Accelerator pedal position
sensor 2)Fully released 0.3 - 0.6V
Fully depressed 1.95 - 2.4V
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EC-540Revision: June 2006
DTC P2A00 A/F SENSOR 1
2007 Versa
DTC P2A00 A/F SENSOR 1PFP:22693
Component DescriptionUBS00QNP
The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is composed an elec-
trode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocar-
bon density in rich.
Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800°C
(1,472°F).
CONSULT-II Reference Value in Data Monitor ModeUBS00QNQ
Specification data are reference values.
On Board Diagnosis LogicUBS00QNR
To judge the malfunction, the A/F signal computed by ECM from the A/F sensor 1 signal is monitored not to be
shifted to LEAN side or RICH side.
PBIB3353E
PBIB3354E
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
Engine: After warming upMaintaining engine speed at
2,000 rpmFluctuates around 2.2V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P2A00
2A00Air fuel ratio (A/F) sensor 1
circuit range/performance
The output voltage computed by ECM from the
A/F sensor 1 signal is shifted to the lean side
for a specified period.
The A/F signal computed by ECM from the A/F
sensor 1 signal is shifted to the rich side for a
specified period.
Air fuel ratio (A/F) sensor 1
Air fuel ratio (A/F) sensor 1 heater
Fuel pressure
Fuel injector
Intake air leaks
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DTC P2A00 A/F SENSOR 1
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DTC Confirmation ProcedureUBS00QNS
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 11V at idle.
WITH CONSULT-II
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 and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-II.
4. Clear the self-learning coefficient by touching “CLEAR”.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and
4,000 rpm for 1 minute under no load.
7. Let engine idle for 1 minute.
8. Keep engine speed between 2,500 and 3,000 rpm for 20 min-
utes.
9. If 1st trip DTC is detected, go to EC-543, "
Diagnostic Procedure"
.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor harness connector.
4. Start engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor (1) harness
connector.
6. Select Service $03 with GST and make sure that DTC P0102 is
detected.
7. Select Service $04 with GST and erase the DTC P0102.
8. Start engine and keep the engine speed between 3,500 and
4,000 rpm for 1 minute under no load.
9. Let engine idle for 1 minute.
10. Keep engine speed between 2,500 and 3,000 rpm for 20 min-
utes.
11. Select Service $07 with GST.
If 1st trip DTC is detected, go to EC-543, "
Diagnostic Procedure" .
PBIB2035E
BBIA0701E
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EC-542Revision: June 2006
DTC P2A00 A/F SENSOR 1
2007 Versa
Wiring Diagram UBS00QNT
BBWA2631E
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DTC P2A00 A/F SENSOR 1
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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.)
Diagnostic ProcedureUBS00QNU
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
3 G A/F sensor 1 heater[Engine is running]
Warm-up condition
Idle speed
(More than 140 seconds after starting
engine)Approximately 2.9 - 8.8V
49 W A/F sensor 1[Engine is running]
Warm-up condition
Engine speed: 2,000 rpmApproximately 1.8V
Output voltage varies with air fuel
ratio.
53 B A/F sensor 1[Ignition switch: ON]Approximately 2.2V
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:Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15
BBIA0698E