2005 INFINITI FX35 vq35de

DTC P1229 SENSOR POWER SUPPLY EC-485
[VQ35DE]
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Revision: 2005 July 2005 FX
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.
Diagnostic ProcedureABS006VT
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to EC-170, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
48 LG Sensor power supply
(EVAP control system pres-
sure sensor) [Ignition switch: ON]
Approximately 5V
49 PU Sensor power supply
(Refrigerant pressure sen-
sor) [Ignition switch: ON]
Approximately 5V
68 BR Sensor power supply
(Power steering pressure
sensor) [Ignition switch: ON]
Approximately 5V
90 L/B Sensor power supply
(APP sensor 1) [Ignition switch: ON]
Approximately 5V
PBIB2625E

EC-486
[VQ35DE]
DTC P1229 SENSOR POWER SUPPLY
Revision: 2005 July 2005 FX
2. CHECK ACCELERATOR PEDAL POSITION SENSOR 1 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 5.
NG >> GO TO 3.
3. CHECK SENSOR POWER SUPPLY CIRCUITS
Check the following.

Harness for short to power and short to ground, between the following terminals.

ECM pin terminal.
OK or NG
OK >> GO TO 4.
NG >> Repair short to ground or short to power in harness or connectors.
4. CHECK COMPONENTS
Check the following.

Refrigerant pressure sensor (Refer to AT C - 9 0 , "COMPONENT INSPECTION" .)

Power steering pressure sensor (Refer to EC-401, "Component Inspection" .)

EVAP control system pressure sensor (Refer to EC-352, "Component Inspection" .)
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning component.
PBIB1580E
Voltage: Approximately 5V
PBIB0914E
ECM terminal Sensor terminal Reference Wiring Diagram
90 APP sensor terminal 6 EC-621
49 Refrigerant pressure sensor terminal 1EC-675
68 PSP sensor terminal 1EC-398
48 EVAP control system pressure sensor terminal 3EC-355

DTC P1229 SENSOR POWER SUPPLY EC-487
[VQ35DE]
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Revision: 2005 July 2005 FX
5. CHECK APP SENSOR
Refer to EC-624, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-96, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-96, "
Throttle Valve Closed Position Learning" .
4. Perform EC-97, "
Idle Air Volume Learning" .
>> INSPECTION END
7. CHECK INTERMITTENT INCIDENT
Refer to EC-163, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END

EC-488
[VQ35DE]
DTC P1271, P1281 A/F SENSOR 1
Revision: 2005 July 2005 FX
DTC P1271, P1281 A/F SENSOR 1PFP:22693
Component DescriptionABS00A9T
The air fuel ratio (A/F) sensor is a planar dual-cell limit current sen-
sor. The sensor element of the air fuel ratio (A/F) sensor is the com-
bination of a Nernst concentration cell (sensor cell) with an oxygen-
pump cell, 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 (0.7 < < air).
The exhaust gas components diffuse through the diffusion gap at the
electrode of the oxygen pump and Nernst concentration cell, where
they are brought to thermodynamic balance.
An electronic circuit controls the pump current through the oxygen-
pump cell so that the composition of the exhaust gas in the diffusion
gap remains constant at = 1. Therefore, the air fuel ratio (A/F) sen-
sor is able to indicate air/fuel ratio by this pumping of current. In
addition, a heater is integrated in the sensor to ensure the required
operating temperature of 700 - 800 °C (1,292 - 1,472 °F).
CONSULT-II Reference Value in Data Monitor ModeABS00A9U
Specification data are reference values.
On Board Diagnosis LogicABS00A9V
To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the air fuel ratio (A/
F) sensor 1 signal is not inordinately low.
DTC Confirmation ProcedureABS00A9W
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. Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-II.
SEF579Z
SEF580Z
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 1.5V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P1271
1271
(Bank 1) Air fuel ratio (A/F) sensor 1
circuit no activity detected

The A/F signal computed by ECM from the
air fuel ratio (A/F) sensor 1 signal is con-
stantly approx. 0V.
Harness or connectors
(The air fuel ratio (A/F) sensor 1 cir-
cuit is open or shorted.)

Air fuel ratio (A/F) sensor 1
P1281
1281
(Bank 2)

DTC P1271, P1281 A/F SENSOR 1 EC-489
[VQ35DE]
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Revision: 2005 July 2005 FX
3. Check “A/F SEN1 (B1)” or “A/F SEN1 (B2)” indication.
If the indication is constantly approx. 0V, go to EC-493, "
Diag-
nostic Procedure" .
If the indication is not constantly approx. 0V, go to next step.
4. Turn ignition switch OFF, wait at least 10 seconds and then restart engine.
5. Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.
6. Maintain the following conditions for about 20 consecutive sec- onds.
NOTE:

Keep the accelerator pedal as steady as possible during the cruising.

If this procedure is not completed within 1 minute after restarting engine at step 4, return to step
4.
7. If 1st trip DTC is displayed, go to EC-493, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
ENG SPEED 1,000 - 3,200 rpm
VHCL SPEED SE More than 40 km/h (25 MPH)
B/FUEL SCHDL 1.5 - 9.0 msec
Gear position Suitable position
SEF581Z

EC-490
[VQ35DE]
DTC P1271, P1281 A/F SENSOR 1
Revision: 2005 July 2005 FX
Wiring DiagramABS00A9X
BANK 1
TBWM0390E

DTC P1271, P1281 A/F SENSOR 1 EC-491
[VQ35DE]
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EC
Revision: 2005 July 2005 FX
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.
TERMI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
16 G A/F sensor 1 (Bank 1) [Engine is running]

Warm-up condition

Idle speed Approximately 3.1V
35 B/R Approximately 2.6V
56 L Approximately 2.3V
75 R/B Approximately 2.3V

EC-492
[VQ35DE]
DTC P1271, P1281 A/F SENSOR 1
Revision: 2005 July 2005 FX
BANK 2
TBWM0391E