Nissan Altima HL32 Hybrid. Manual - part 311

EC-228

< COMPONENT DIAGNOSIS >

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P0172 FUEL INJECTION SYSTEM FUNCTION

P0172 FUEL INJECTION SYSTEM FUNCTION

DTC Logic

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DTC DETECTION LOGIC

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 the A/F sensors 1. The ECM calcu-

lates 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 lights up the MIL (2 trip detection logic).

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing the next test.

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.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE-II

1. Clear the mixture ratio self-learning value. Refer to 

EC-18, "MIXTURE RATIO SELF-LEARNING VALUE

CLEAR : Special Repair Requirement"

.

2. Activate “INSPECTION MODE 1” (

HBC-104

) to start engine, and let engine idle for at least 5 minutes.

3. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-229, "Diagnosis Procedure"

.

NO

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE-III

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON (READY).

3. 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.

4. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-229, "Diagnosis Procedure"

.

NO

>> INSPECTION END

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

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 leaks
• Incorrect fuel pressure
• Mass air flow sensor

VECL SPEED SE

80 - 120 km/h (50 mph - 75 mph)

P0172 FUEL INJECTION SYSTEM FUNCTION

EC-229

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Diagnosis Procedure

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1.

CHECK EXHAUST GAS LEAK

1. Activate “INSPECTION MODE 1” (

HBC-104

) to start engine.

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

Is exhaust gas leak detected?

YES

>> Repair or replace.

NO

>> GO TO 2.

2.

CHECK FOR INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?

YES

>> Repair or replace.

NO

>> GO TO 3.

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 the continuity between A/F sensor 1 harness connector and ECM harness connector.

5. Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.

6. Also check harness for short to power.
Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.

CHECK FUEL PRESSURE

1. Check fuel pressure. Refer to 

EC-465, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> GO TO 5.

5.

 DETECT MALFUNCTIONING PART

Check fuel hoses and fuel tubes for clogging.

JMBIA0163GB

A/F sensor 1

ECM

Continuity

Connector Terminal Connector Terminal

F44

1

F14

45

Existed

2

49

A/F sensor 1

ECM

Ground

Continuity

Connector Terminal Connector Terminal

F44

1

F14

45

Ground Not existed

2

49

EC-230

< COMPONENT DIAGNOSIS >

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P0172 FUEL INJECTION SYSTEM FUNCTION

Is the inspection result normal?

YES

>> Replace “fuel filter and fuel pump assembly”.

NO

>> Repair or replace

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.

3. For specification, refer to 

EC-470, "Mass Air Flow Sensor"

.

With GST

1. Install all removed parts.

2. Check mass air flow sensor signal in “Service $01” with GST.

3. For specification, refer to 

EC-470, "Mass Air Flow Sensor"

.

Is the measurement value within the specification?

YES

>> GO TO 7.

NO

>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or

grounds. Refer to 

EC-144, "DTC Logic"

.

7.

CHECK FUNCTION OF FUEL INJECTOR

With CONSULT-III

1. Turn ignition ON (READY).

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

3. Make sure that each circuit produces a momentary engine speed drop.

Without CONSULT-III

1. Activate “INSPECTION MODE 1” (

HBC-104

) to start engine.

2. Listen to each fuel injector operating sound.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Perform trouble diagnosis for FUEL INJECTOR, refer to

EC-237, "Diagnosis Procedure"

.

8.

CHECK FUELINJECTOR

1. Remove fuel injector assembly. Refer to 

EM-35, "Removal and Installation"

.

Keep fuel hose and all fuel injectors connected to fuel tube.

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 injectors.

6. Turn ignition switch ON (READY).

7. Depress the accelerator pedal to crank engine.

Make sure fuel does not drip from fuel injector.

NOTE:

If step 7 performed, a certain DTC may be detected.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one. 

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Clicking noise should be heard.

PBIB3332E

P0181 FTT SENSOR

EC-231

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P0181 FTT SENSOR

Description

INFOID:0000000004211465

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 95 (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 transis-
tor. Use a ground other than ECM terminals, such as the ground.

DTC Logic

INFOID:0000000004211466

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing the next test.

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.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE-I

1. Turn ignition switch ON and wait at least 10 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-232, "Diagnosis Procedure"

.

NO

>> GO TO 3.

3.

CHECK ENGINE COOLANT TEMPERATURE

With CONSULT-III

1. Select “COOLAN TEMP/S” in “DATA MONITOR” mode with CONSULT-III.

2. Check “COOLAN TEMP/S” value.

With GST

Follow the procedure “With CONSULT-III” above.
“COOLAN TEMP/S” less than 60

°C (140°F)?

YES

>> INSPECTION END

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

Fuel tank temperature 
sensor circuit range/per-
formance

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