Nissan Pathfinder (2009 year). Manual - part 331

EC-662

< COMPONENT DIAGNOSIS >

[VK56DE]

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

On Board Diagnosis Logic

INFOID:0000000003936590

With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from A/F sensor 1. The ECM calculates
the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (the actual mixture ratio is too rich), the ECM
judges the condition as the fuel injection system malfunction and illuminates the MIL (2 trip detection logic).

DTC Confirmation Procedure

INFOID:0000000003936591

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

 WITH CONSULT-III

1.

Start engine and warm it up to normal operating temperature.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Turn ignition switch OFF and wait at least 10 seconds.

5.

Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.

6.

Clear the self-learning control coefficient by touching “CLEAR”.

7.

Start engine.
If it is difficult to start engine, the fuel injection system has a malfunction.
Performing the following procedure is advised.

a.

Crank engine while depressing accelerator pedal.
NOTE:
When depressing accelerator pedal three-fourths (3/4) or more, the control system does not start the
engine. Do not depress accelerator pedal too much.

b.

If engine starts, go to 

EC-663, "Diagnosis Procedure"

.

If engine does not start, remove spark plugs and check for fouling, etc.

8.

Keep engine at idle for at least 5 minutes.

9.

Check 1st trip DTC.

10. The 1st trip DTC P0172 or P0175 should be detected at this stage, if a malfunction exists. If so, go to 

EC-

663, "Diagnosis Procedure"

.

NOTE:
If 1st trip DTC is not detected during above procedure, performing the following procedure is advised.

a.

Turn ignition switch OFF and wait at least 10 seconds.

b.

Start engine.

Sensor

Input signal to ECM

ECM function

Actuator

A/F sensor 1

Density of oxygen in exhaust gas
(Mixture ratio feedback signal)

Fuel injection control

Fuel injector

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0172
0172
(Bank 1)

Fuel injection system too 
rich

• Fuel injection system does not operate properly.
• The amount of mixture ratio compensation is too 

large. (The mixture ratio is too rich.)

• A/F sensor 1
• Fuel injector
• Exhaust gas leakage
• Incorrect fuel pressure
• Mass air flow sensor

P0175
0175
(Bank 2)

2009 Pathfinder

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

EC-663

< COMPONENT DIAGNOSIS >

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c.

Maintain the following conditions for at least 10 consecutive minutes.
Hold the accelerator pedal as steady as possible.

CAUTION:

Always drive vehicle at a safe speed.

d.

Check 1st trip DTC.

e.

If 1st trip DTC is detected, go to 

EC-663, "Diagnosis Procedure"

.

 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.

Turn ignition switch ON.

4.

Turn ignition switch OFF and wait at least 10 seconds.

5.

Disconnect mass air flow sensor (1) harness connector.
•

 : Vehicle front

6.

Restart engine and let it idle for at least 5 seconds.

7.

Stop engine and reconnect mass air flow sensor harness con-
nector.

8.

Select Service $03 with GST. Check that DTC P0102 is
detected.

9.

Select Service $04 with GST and erase the DTC P0102.

10. Start engine.

If it is difficult to start engine, the fuel injection system has a mal-
function.
Performing the following procedure is advised.

a.

Crank engine while depressing accelerator pedal.
NOTE:
When depressing accelerator pedal three-fourths (3/4) or more, the control system does not start the
engine. Do not depress accelerator pedal too much.

b.

If engine starts, go to 

EC-663, "Diagnosis Procedure"

.

If engine does not start, remove spark plugs and check for fouling, etc.

11. Keep engine at idle for at least 5 minutes.
12. Check 1st trip DTC.

13. The 1st trip DTC P0172 or P0175 should be detected at this stage, if a malfunction exists. If so, go to 

EC-

663, "Diagnosis Procedure"

.

NOTE:
If 1st trip DTC is not detected during above procedure, performing the following procedure is advised.

a.

Turn ignition switch OFF and wait at least 10 seconds.

b.

Start engine.

c.

Maintain the following conditions for at least 10 consecutive minutes.
Hold the accelerator pedal as steady as possible.

CAUTION:

Always drive vehicle at a safe speed.

d.

Check 1st trip DTC.

e.

If 1st trip DTC is detected, go to 

EC-663, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000003936592

1.

CHECK EXHAUST GAS LEAKAGE

1.

Start engine and run it at idle.

VHCL SPEED SE

50 - 120 km/h (31 - 75 MPH)

VHCL SPEED SE

50 - 120 km/h (31 - 75 MPH)

ALBIA0353ZZ

2009 Pathfinder

EC-664

< COMPONENT DIAGNOSIS >

[VK56DE]

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

2.

Listen for an exhaust gas leakage before three way catalyst (manifold).

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace malfunctioning part.

2.

CHECK FOR INTAKE AIR LEAKAGE

Listen for an intake air leakage after the mass air flow sensor.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace malfunctioning part.

3.

CHECK AIR FUEL RATIO SENSOR 1 INPUT SIGNAL CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect corresponding air fuel ratio (A/F) sensor 1 harness connector.

3.

Disconnect ECM harness connector.

4.

Check harness continuity between A/F sensor 1 terminals and ECM terminals as per the following.
Refer to Wiring Diagram.

5.

Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.

PBIB1216E

ALBIA0360ZZ

1.

A/F sensor 1 (bank 2) harness connector

2.

A/F sensor 1 (bank 2)

3.

A/F sensor 1 (bank 1)

4.

A/F sensor 1 (bank 1) harness connector

: Vehicle front

A/F sensor 1 terminal

ECM terminal

Bank 1

1

35

2

56

Bank 2

1

16

2

75

Continuity should exist.

2009 Pathfinder

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

EC-665

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6.

Also check harness for 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-951, "Fuel Pressure Check"

.

2.

Install fuel pressure gauge and check fuel pressure. Refer to 

EC-951, "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-869, "Diagnosis Procedure"

.)

• Fuel pressure regulator (Refer to 

EC-951, "Fuel Pressure Check"

.)

>> Repair or replace malfunctioning part.

6.

CHECK MASS AIR FLOW SENSOR

 With CONSULT-III

1.

Install all removed parts.

2.

Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-III.

 With GST

1.

Install all removed parts.

2.

Check mass air flow sensor signal in Service $01 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

grounds. Refer to 

EC-595, "Diagnosis Procedure"

.

7.

CHECK FUNCTION OF FUEL INJECTOR

 With CONSULT-III

1.

Start engine.

2.

Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-III.

3.

Check that each circuit produces a momentary engine speed drop.

 Without CONSULT-III

1.

Start engine.

Bank 1

Bank 2

A/F sensor 1 terminal

ECM terminal

A/F sensor 1 terminal

ECM terminal

1

35

1

16

2

56

2

75

Continuity should not exist.

At idling: Approximately 350 kPa (3.57 kg/cm

2

, 51 psi)

3.0 - 9.0 g·m/sec:

At idling

9.0 - 28.0 g·m/sec:

At 2,500 rpm

3.0 - 9.0 g·m/sec:

At idling

9.0 - 28.0 g·m/sec:

At 2,500 rpm

2009 Pathfinder

EC-666

< COMPONENT DIAGNOSIS >

[VK56DE]

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

2.

Listen to each fuel injector operating sound.

OK or NG

OK

>> GO TO 8.

NG

>> Perform trouble diagnosis for FUEL INJECTOR, refer to

EC-866, "Diagnosis Procedure"

.

8.

CHECK FUEL INJECTOR

1.

Remove fuel injector assembly. Refer to 

EM-182, "Removal and Installation"

.

Keep fuel hose and all fuel injectors connected to fuel injector gallery.

2.

Confirm that the engine is cooled down and there are no fire hazards near the vehicle.

3.

Disconnect all fuel injector harness connectors.

4.

Disconnect all ignition coil harness connectors.

5.

Prepare pans or saucers under each fuel injector.

6.

Crank engine for approximately 3 seconds.
Check that fuel does not drip from fuel injector.

OK or NG

OK (Does not drip.)>>GO TO 9.
NG (Drips.)>>Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one. 

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-49, "Intermittent Incident"

.

>> INSPECTION END

Clicking noise should be heard.

PBIB1986E

2009 Pathfinder

P0181 FTT SENSOR

EC-667

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P0181 FTT SENSOR

Component Description

INFOID:0000000004333359

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.

<Reference data>

*: These data are reference values and are measured between ECM terminal 107
(Fuel tank temperature sensor) and ground.

CAUTION:

Never 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 Logic

INFOID:0000000003936594

DTC Confirmation Procedure

INFOID:0000000003936595

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

 WITH CONSULT-III

1.

Turn ignition switch ON and wait at least 10 seconds.

2.

Check 1st trip DTC.
If 1st trip DTC is detected, go to 

EC-668, "Diagnosis Procedure"

.

If 1st trip DTC is not detected, go to the following step.

3.

Select “DATA MONITOR” mode with CONSULT-III.

4.

Check “COOLAN TEMP/S” indication.
If the “COOLAN TEMP/S” is less than 60

°

C (140

°

F), the result will be OK.

If the “COOLAN TEMP/S” indication is above 60

°

C (140

°

F), go to the following step.

5.

Cool engine down until “COOLAN TEMP/S” indication is less than 60

°

C (140

°

F).

BBIA0545E

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 signals 
from engine coolant temperature sensor and in-
take air temperature sensor.

• Harness or connectors

(The sensor circuit is open or shorted)

• Fuel tank temperature sensor

2009 Pathfinder

EC-668

< COMPONENT DIAGNOSIS >

[VK56DE]

P0181 FTT SENSOR

6.

Wait at least 10 seconds.

7.

Check 1st trip DTC.

8.

If 1st trip DTC is detected, go to 

EC-668, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000004333361

1.

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-III or tester.

OK or NG

OK

>> GO TO 3.

NG

>> GO TO 2.

2.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors C1, E41
• Harness for open or short between ECM and “fuel level sensor unit and fuel pump”

>> Repair harness or connector.

3.

CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check harness continuity between “fuel level sensor unit and fuel pump” terminal 3 and ground.
Refer to Wiring Diagram.

3.

Also check harness for short to power.

OK or NG

OK

>> GO TO 5.

NG

>> GO TO 4.

4.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors C1, E41
• Harness for open or short between “fuel level sensor unit and fuel pump” and ground

BBIA0545E

Voltage: Approximately 5 V

PBIB0932E

Continuity should exist.

2009 Pathfinder

P0181 FTT SENSOR

EC-669

< COMPONENT DIAGNOSIS >

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>> Repair open circuit or short to power in harness or connector.

5.

CHECK FUEL TANK TEMPERATURE SENSOR

Refer to 

EC-669, "Component Inspection"

.

OK or NG

OK

>> GO TO 6.

NG

>> Replace “fuel level sensor unit fuel pump”.

6.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-49, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000004333360

FUEL TANK TEMPERATURE SENSOR

1.

Remove “fuel level sensor unit and fuel pump”.

2.

Check resistance between “fuel level sensor unit and fuel pump”
terminals 3 and 4 by heating with hot water as shown in the fig-
ure.

3.

If NG, replace “fuel level sensor unit and fuel pump”.

Temperature [

°

C (

°

F)]

Resistance (k

Ω

)

20 (68)

2.3 - 2.7

 50 (122)

0.79 - 0.90

SEF476YA

2009 Pathfinder