2005 INFINITI FX35 vq35de

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION EC-261
[VQ35DE]
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Revision: 2005 July 2005 FX
BANK 2
TBWM0387E

EC-262
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2005 July 2005 FX
Diagnostic ProcedureABS006P5
1. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst 1.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
PBIB1922E

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION EC-263
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Revision: 2005 July 2005 FX
3. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals. Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
6. 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.
Bank 1 A/F sensor 1 terminal ECM terminal
116
275
535
656
Bank 2 176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 116176
275277
535557
656658
Continuity should not exist.
PBIB2190E

EC-264
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2005 July 2005 FX
4. CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-99, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-99, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Fuel pump and circuit (Refer to EC-668, "FUEL PUMP CIRCUIT" .)

Fuel pressure regulator (Refer to EC-99, "FUEL PRESSURE CHECK" .)
>> 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 Service $01 with GST.
OK or NG
OK (With CONSULT-II)>>GO TO 7.
OK (Without CONSULT-II)>>GO TO 8.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or ground. Refer to EC-186, "
DTC P0101 MAF SENSOR" .
7. CHECK FUNCTION OF INJECTOR
With CONSULT-II
1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-II.
3. Make sure that each circuit produces a momentary engine speed drop.
OK or NG
OK >> GO TO 10.
NG >> Perform trouble diagnosis for INJECTOR CIRCUIT, refer to EC-661, "
INJECTOR CIRCUIT" .
At idling: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
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
PBIB0133E

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION EC-265
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Revision: 2005 July 2005 FX
8. CHECK FUNCTION OF INJECTOR-I
Without CONSULT-II
1. Stop engine.
2. Disconnect harness connector F50, F251
3. Turn ignition switch ON.
4. Check voltage between harness connector F50 terminal 5 and ground with CONSULT-II or tester.
5. Turn ignition switch OFF.
6. Disconnect ECM harness connector.
7. Check harness continuity between harness connector F50 and ECM as follows.
Refer to Wiring Diagram.
8. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Perform trouble diagnosis for INJECTOR CIRCUIT, refer to EC-661, "
INJECTOR CIRCUIT" .
PBIB2624E
Voltage: Battery voltage
Cylinder Harness connector F50
terminal ECM terminal
1623
2442
3222
4341
5121
6740
Continuity should exist.
PBIB2323E

EC-266
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2005 July 2005 FX
9. CHECK FUNCTION OF INJECTOR-II
Provide battery voltage between harness connector F251 as follows
and then interrupt it. Listen to each injector operating sound.
OK or NG
OK >> GO TO 10.
NG >> Perform trouble diagnosis for INJECTOR CIRCUIT, refer to EC-661, "
INJECTOR CIRCUIT" .
10. CHECK INJECTOR
1. Remove injector assembly. Refer to EM-45, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all injectors connected to injector gallery.
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Reconnect all harness connectors disconnected.
4. Disconnect all injector harness connectors.
5. Disconnect all ignition coil harness connectors.
6. Prepare pans or saucers under each injectors.
7. Crank engine for about 3 seconds. Make sure fuel does not drip from injector.
OK or NG
OK (Does not drip.)>>GO TO 11.
NG (Drips.)>>Replace the injectors from which fuel is dripping. Always replace O-ring with new one.
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-163, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Cylinder Harness connector F251 terminal
(+) (–)
156
254
352
453
551
657
Operating sound should exist.
PBIB2497E

DTC P0181 FTT SENSOR EC-267
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Revision: 2005 July 2005 FX
DTC P0181 FTT SENSORPFP:22630
Component DescriptionABS006P6
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.

*: This data is reference value and is 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 LogicABS006P7
DTC Confirmation ProcedureABS006P8
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-270, "
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-270, "
Diagnostic Procedure" .
PBIB1572E
Fluid temperature
° C ( °F) Voltage*
V Resistance
k Ω
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
0181 Fuel tank temperature
sensor circuit range/
performance Rationally 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

Unified meter and A/C amp.
SEF174Y

EC-268
[VQ35DE]
DTC P0181 FTT SENSOR
Revision: 2005 July 2005 FX
WITH GST
Follow the procedure “WITH CONSULT-II” above.