Page 651 of 720

DTC P2138 APP SENSOR
EC-651
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Revision: 2006 November2007 350Z
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureNBS000HG
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 8V at idle.
WITH CONSULT-III
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-654, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138Accelerator pedal posi-
tion sensor circuit
range/performanceRationally 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.)
Harness or connectors
(APP sensor 2 dircuit is open or
shorted.)
[CKP sensor (POS) circuit is open or
shorted.]
[CMP sensor (PHASE) (bank 2) circuit is
shorted.]
[EVT control position sensor (bank 2) cir-
cuit is shorted.]
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
Accelerator pedal position sensor
(APP sensor 1 and 2)
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
(bank 2)
Exhaust valve timing control position
sensor (bank 2)
EVAP control system pressure sensor
Refrigerant pressure sensor
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.
Page 653 of 720

DTC P2138 APP SENSOR
EC-653
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Revision: 2006 November2007 350Z
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
46 R/BSensor power supply
[Crankshaft position sensor
(POS)][Ignition switch: ON]5V
64 W/GSensor power supply
[Camshaft position sensor
(PHASE) (bank 2), Exhaust
valve timing control position
sensor (bank 2)][Ignition switch: ON]5V
97 RAccelerator pedal position
sensor 1[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully released0.5 - 1.0V
[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully depressed3.9 - 4.7V
98 SBAccelerator pedal position
sensor 2[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully released0.15 - 0.60V
[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully depressed1.95 - 2.40V
99 LSensor power supply
(Accelerator pedal position
sensor 1)[Ignition switch: ON]5V
100 WSensor ground
(Accelerator pedal position
sensor 1)[Engine is running]
Warm-up condition
Idle speed0V
103 GSensor power supply
(Accelerator pedal position
sensor 2)[Ignition switch: ON]5V
104 GYSensor ground
(Accelerator pedal position
sensor 2)[Engine is running]
Warm-up condition
Idle speed0V
107 BRSensor power supply
(EVAP control system pres-
sure sensor)[Ignition switch: ON]5V
111 O RSensor power supply
(Refrigerant pressure sen-
sor)[Ignition switch: ON]5V
Page 659 of 720

DTC P2A00, P2A03 A/F SENSOR 1
EC-659
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Revision: 2006 November2007 350Z
DTC P2A00, P2A03 A/F SENSOR 1PFP:22693
Component DescriptionNBS006V7
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-III Reference Value in Data Monitor ModeNBS000EF
Specification data are reference values.
On Board Diagnosis LogicNBS000EG
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.
PBIB3559E
PBIB3354E
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)
Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 2.2V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P2A00
2A00
(Bank 1)
Air 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 output voltage 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 P2A03
2A03
(Bank 2)
Page 660 of 720

EC-660
DTC P2A00, P2A03 A/F SENSOR 1
Revision: 2006 November2007 350Z
DTC Confirmation ProcedureNBS000EH
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-III
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-III.
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 minutes.
9. Check 1st trip DTC.
10. If 1st trip DTC is detected, go to EC-665, "
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 (bank 1) harness connector.
4. Start engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor (bank 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 minutes.
11. Select Service $07 with GST.
If 1st trip DTC is detected, go to EC-665, "
Diagnostic Procedure" .
1. Mass air flow sensor (with intake air
temperature sensor) (bank 1)2. Mass air flow sensor (with intake air
temperature sensor) (bank 2)
PBIB3501E
Page 662 of 720
EC-662
DTC P2A00, P2A03 A/F SENSOR 1
Revision: 2006 November2007 350Z
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-III.
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.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
1W/RA/F sensor 1 heater
(bank 1)[Engine is running]
Warm-up condition
Idle speed
(More than 140 seconds after starting
engine)2.9 - 8.8V
57 L A/F sensor 1 (bank 1)[Ignition switch: ON]2.2V
61 R A/F sensor 1 (bank 1)[Ignition switch: ON]
Warm-up condition
Engine speed: 2,000 rpm1.8V
Output voltage varies with air
fuel ratio.
PBIB3538E
Page 664 of 720
EC-664
DTC P2A00, P2A03 A/F SENSOR 1
Revision: 2006 November2007 350Z
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-III.
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.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
5GY/LA/F sensor 1 heater
(bank 2)[Engine is running]
Warm-up condition
Idle speed
(More than 140 seconds after starting
engine)2.9 - 8.8
65 PU A/F sensor 1 (bank 2)[Ignition switch: ON]2.2V
66 LG A/F sensor 1 (bank 2)[Ignition switch: ON]
Warm-up condition
Engine speed: 2,000 rpm1.8V
Output voltage varies with air
fuel ratio.
PBIB3538E
Page 666 of 720
EC-666
DTC P2A00, P2A03 A/F SENSOR 1
Revision: 2006 November2007 350Z
2. RETIGHTEN AIR FUEL RATIO SENSOR 1
1. Loosen and retighten the air fuel ratio (A/F) sensor 1.
>> GO TO 3.
3. CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
1. A/F sensor 1 (bank1) 2. A/F sensor 1 (bank 2)
:Vehicle front
Tightening torque: 50 N-m (5.1 kg-m, 37 ft-lb)
PBIB3517E
Page 667 of 720

DTC P2A00, P2A03 A/F SENSOR 1
EC-667
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Revision: 2006 November2007 350Z
4. CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor (bank 1) harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor (bank 1) harness connector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-61, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFOR-
MATION" .
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-324, "DTC
P0171, P0174 FUEL INJECTION SYSTEM FUNCTION" or EC-334, "DTC P0172, P0175 FUEL
INJECTION SYSTEM FUNCTION" .
No >> GO TO 5.
1. Mass air flow sensor (with intake air
temperature sensor) (bank 1)2. Mass air flow sensor (with intake air
temperature sensor) (bank 2)
PBIB3501E