2004 INFINITI FX35 Temperature sensor

EC-924
[VK45DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
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. Then
restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Select MODE 3 with GST. Make sure DTC P0102 is detected.
6. Select MODE 4 with GST and erase the DTC P0102.
7. Start engine again and let it idle for at least 10 minutes.
8. Select MODE 7 with GST. The 1st trip DTC P0172 or P0175
should be detected at this stage, if a malfunction exists. If so, go
to EC-927, "
Diagnostic Procedure" .
9. If it is difficult to start engine at step 7, the fuel injection system
has a malfunction.
10. Crank engine while depressing accelerator pedal.
If engine starts, go to EC-927, "
Diagnostic Procedure" . If engine does not start, remove ignition plugs and
check for fouling, etc.
PBIB1502E

DTC P0181 FTT SENSOR
EC-931
[VK45DE]
C
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MA
EC
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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MA
EC
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.

EC-936
[VK45DE]
DTC P0181 FTT SENSOR
Revision: 2004 November 2004 FX35/FX45
Component InspectionABS00C47
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water or heat gun as
shown in the figure.
Removal and InstallationABS00C48
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Temperature °C (°F) Resistance kΩ
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E

DTC P0182, P0183 FTT SENSOR
EC-937
[VK45DE]
C
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H
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K
L
MA
EC
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

DTC P0182, P0183 FTT SENSOR
EC-939
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureABS00C4D
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

EC-940
[VK45DE]
DTC P0182, P0183 FTT SENSOR
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.