2004 INFINITI FX35 ground

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-919
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
3. CHECK HEATED OXYGEN SENSOR 1 CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect corresponding heated oxygen sensor 1 (HO2S1) harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
6. Check harness continuity between HO2S1 terminal 4 and ECM terminal 78.
7. 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 FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-700, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-701, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
DTCTe r m i n a l s
Bank
ECM Sensor
P0171 16 1 1
P0174 35 1 2
Continuity should exist.
PBIB1521E
DTCTe r m i n a l s
Bank
ECM Sensor
P0171 16 1 1
P0174 35 1 2
Continuity should not exist.
Continuity should exist.
At idling: 350 kPa (3.57 kg/cm2 , 51 psi)

EC-920
[VK45DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
5. DETECT MALFUNCTIONING PART
Check the following.

Fuel pump and circuit (Refer to EC-1280 .)

Fuel pressure regulator (Refer to EC-701 .)

Fuel lines

Fuel filter for clogging
>> Repair or replace.
6. CHECK MASS AIR FLOW SENSOR
With CONSULT-II
1. Install all removed parts.
2. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-II.
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in MODE 1 with GST.
OK or NG
OK >> GO TO 8.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-822, "
DTC P0101 MAF SENSOR" . 2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm

EC-928
[VK45DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
3. CHECK HEATED OXYGEN SENSOR 1 CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect corresponding heated oxygen sensor 1 (HO2S1) harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
6. Check harness continuity between HO2S1 terminal 4 and ECM terminal 78.
7. 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 FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-700, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-701, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
DTCTerminals
Bank
ECM Sensor
P0172 16 1 1
P0175 35 1 2
Continuity should exist.
PBIB1521E
DTCTerminals
Bank
ECM Sensor
P0172 16 1 1
P0175 35 1 2
Continuity should not exist.
Continuity should exist.
At idling: 350 kPa (3.57 kg/cm2 , 51 psi)

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-929
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
5. DETECT MALFUNCTIONING PART
Check the following.

Fuel pump and circuit (Refer to, EC-1280 .)

Fuel pressure regulator (Refer to EC-701 .)
>> Repair or replace.
6. CHECK MASS AIR FLOW SENSOR
With CONSULT-II
1. Install all removed parts.
2. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-II.
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in MODE 1 with GST.
OK or NG
OK >> GO TO 7.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-822, "
DTC P0101 MAF SENSOR" . 2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm

DTC P0181 FTT SENSOR
EC-931
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0181 FTT SENSORPFP:22630
Component DescriptionABS00C42
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: These data are reference values and are measured between ECM terminal 107
(Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicABS00C43
DTC Confirmation ProcedureABS00C44
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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 10 seconds.
If the result is NG, go to EC-934, "
Diagnostic Procedure" .
If the result is OK, go to following step.
4. Check “COOLAN TEMP/S” value.
If “COOLAN TEMP/S” is less than 60°C (140°F), the result will
be OK.
If “COOLAN TEMP/S” is above 60°C (140°F), go to the following
step.
5. Cool engine down until “COOLAN TEMP/S” is less than 60°C
(140°F).
6. Wait at least 10 seconds.
7. If 1st trip DTC is detected, go to EC-934, "
Diagnostic Procedure" .
PBIB1507E
Fluid temperature
°C (°F)Voltage*
VResistance
kΩ
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0181
0181Fuel tank temperature
sensor circuit range/
performanceRationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage sig-
nals from engine coolant temperature sensor
and intake air temperature sensor.

Harness or connectors
(The sensor circuit is open or shorted)

Fuel tank temperature sensor
SEF174Y

EC-934
[VK45DE]
DTC P0181 FTT SENSOR
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureABS00C46
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-32, "
SELF-DIAGNOSTIC RESULTS" .
OK or NG
OK >> GO TO 3.
NG >> Go to DI-20, "
Fuel Level Sensor Signal Inspection 1" .
3. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect “fuel level sensor unit and fuel pump” harness con-
nector.
3. Turn ignition switch ON.
4. Check voltage between “fuel level sensor unit and fuel pump”
terminal 4 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
PBIB2195E
PBIB1507E
Voltage: Approximately 5V
PBIB0932E

DTC P0181 FTT SENSOR
EC-935
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors B1, M11

Harness for open or short between ECM and “fuel level sensor unit and fuel pump”
>> Repair open circuit or short to ground or short to power in harness or connector.
5. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “unified meter and A/C amp.” harness connector.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors B1, M11

Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C
amp.”
>> Repair open circuit or short to power in harness or connector.
7. CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-936, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace fuel level sensor unit.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.

DTC P0182, P0183 FTT SENSOR
EC-937
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0182, P0183 FTT SENSORPFP:22630
Component DescriptionABS00C49
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: These data are reference values and are measured between ECM terminal 107
(Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicABS00C4A
DTC Confirmation ProcedureABS00C4B
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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-939, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
PBIB1507E
Fluid temperature
°C (°F)Voltage*
VResistance
kΩ
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0182
0182Fuel tank temperature
sensor circuit low inputAn excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Fuel tank temperature sensor P0183
0183Fuel tank temperature
sensor circuit high inputAn excessively high voltage from the sensor is
sent to ECM.
SEF174Y