2008 INFINITI FX35 sensor

EC-416
< SERVICE INFORMATION >[VQ35DE]
DTC P0550 PSP SENSOR
3. Check voltage between PSP sensor terminal 1 and ground with
CONSULT-III 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.
3.CHECK POWER STEERING PRESSURE SENSO R GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between PSP sensor terminal 3 and ECM terminal 67. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK POWER STEERING PRESSURE SENSOR INPU T SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 12 and PSP sensor terminal 2. Refer to Wiring Diagram.
2. 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 POWER STEERING PRESSURE SENSOR
Refer to EC-416, "
Component Inspection".
OK or NG
OK >> GO TO 6.
NG >> Replace power steering pressure sensor.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
Component InspectionINFOID:0000000001326260
POWER STEERING PRESSURE SENSOR
1. Reconnect all harness connectors disconnected.
2. Start engine and let it idle. Voltage: Approximately 5V
PBIB0188E
Continuity should exist.
Continuity should exist.
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DTC P0550 PSP SENSOREC-417
< SERVICE INFORMATION > [VQ35DE]
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3. Check voltage between ECM terminal 12 and ground under the
following conditions.
Removal and InstallationINFOID:0000000001326261
POWER STEERING PRESSURE SENSOR
Refer to PS-37.
Condition Voltage
Steering wheel: Being turned 0.5 - 4.5V
Steering wheel: Not being turned 0.4 - 0.8V
MBIB0126E
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EC-424
< SERVICE INFORMATION >[VQ35DE]
DTC P0643 SENSOR POWER SUPPLY
DTC P0643 SENSOR POWER SUPPLY
On Board Diagn
osis LogicINFOID:0000000001326271
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000001326272
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, 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.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-426, "
Diagnosis Procedure".
DTC No.Trouble diagnosis
name DTC detecting condition Possible cause
P0643
0643 Sensor power supply
circuit short ECM detects a voltage of power source for
sensor is excessively low or high.  Harness or connectors
(APP sensor 1 circuit is shorted.)
(PSP sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is short-
ed.)
(EVAP control system pressure sensor circuit
is shorted.)
 Accelerator pedal position sensor (APP sensor 1)
 EVAP control system pressure sensor
 Power steering pressure sensor
 Refrigerant pressure sensor
Engine operation condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) b y the return
spring.
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DTC P0643 SENSOR POWER SUPPLYEC-425
< SERVICE INFORMATION > [VQ35DE]
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Wiring DiagramINFOID:0000000001326273
Specification data are reference values
and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals wh en measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground ot her than ECM terminals, such as the ground.
TBWM1400E
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EC-426
< SERVICE INFORMATION >[VQ35DE]
DTC P0643 SENSOR POWER SUPPLY
Diagnosis Procedure
INFOID:0000000001326274
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-144, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT-I
TER-
MI-
NAL
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
82 B/W Sensor ground
(APP sensor 1, ASCD steer-
ing switch, ICC steering
switch) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
83 G/OR Sensor ground
(APP sensor 2) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
90 L/B Sensor power supply
(APP sensor 1)
[Ignition switch: ON]
Approximately 5V
91 G Sensor power supply
(APP sensor 2) [Ignition switch: ON]
Approximately 5V
98 Y/R Accelerator pedal position
sensor 2 [Ignition switch: ON]
 Engine stopped
 Accelerator pedal: Fully released
0.15 - 0.60V
[Ignition switch: ON]
 Engine stopped
 Accelerator pedal: Fully depressed 1.95 - 2.40V
106 OR Accelerator pedal position
sensor 1 [Ignition switch: ON]
 Engine stopped
 Accelerator pedal: Fully released
0.5 - 1.0V
[Ignition switch: ON]
 Engine stopped
 Accelerator pedal: Fully depressed 3.9 - 4.7V
PBIB2625E
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DTC P0643 SENSOR POWER SUPPLYEC-427
< SERVICE INFORMATION > [VQ35DE]
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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-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUITS
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.
4.CHECK COMPONENTS
Check the following.
 Refrigerant pressure sensor (Refer to ATC-69, "
Magnet Clutch Circuit".)
 Power steering pressure sensor (Refer to EC-416, "
Component Inspection".)
 EVAP control system pressure sensor (Refer to EC-373, "
Component Inspection".)
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning component.
5.CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-511, "
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-85, "
Accelerator Pedal Released Position Learning".
3. Perform EC-85, "
Throttle Valve Closed Position Learning".
4. Perform EC-85, "
Idle Air Volume Learning".
PBIB1580E
Voltage: Approximately 5V
PBIB0914E
ECM terminal Sensor terminal Reference Wiring Diagram
90 APP sensor terminal 6 EC-508
49 Refrigerant pressure sensor terminal 1EC-582
68 PSP sensor terminal 1EC-414
48 EVAP control system pressure sensor terminal 3EC-377
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EC-428
< SERVICE INFORMATION >[VQ35DE]
DTC P0643 SENSOR POWER SUPPLY
>>
INSPECTION END
7.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
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EC-434
< SERVICE INFORMATION >[VQ35DE]
DTC P1148, P1168 CLO
SED LOOP CONTROL
DTC P1148, P1168 CLOSED LOOP CONTROL
On Board Diagnosis LogicINFOID:0000000001326282
These self-diagnoses have the one trip detection logic.
NOTE:
DTC P1148 or P1168 is displayed with another DTC for air fuel ratio (A/F) sensor 1.
Perform the trouble diagnosis for the corresponding DTC.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1148
11 4 8
(Bank 1) Closed loop control
function The closed loop control function for bank 1 does
not operate even when vehicle is driving in the
specified condition.
 Harness or connectors
[Air fuel ratio (A/F) sensor 1 circuit is open
or shorted.]
 Air fuel ratio (A/F) sensor 1
 Air fuel ratio (A/F) sensor 1 heater
P1168
11 6 8
(Bank 2) The closed loop control function for bank 2 does
not operate even when vehicle is driving in the
specified condition.
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