Nissan Qashqai J11. Manual - part 315

P0172 FUEL INJECTION SYSTEM FUNCTION

ECM-237

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

C

D

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G

H

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A

ECM

N

P

O

YES

>> Repair or replace malfunctioning part.

NO

>> GO TO 2.

2.

CHECK FOR INTAKE AIR LEAKAGE

1.

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

2.

Check PCV hose connection.

Is intake air leakage detected?

YES

>> Repair or replace malfunctioning part.

NO

>> GO TO 3.

3.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

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 and ground, or ECM harness connector
and ground.

6.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace malfunctioning part.

4.

CHECK FUEL PRESSURE

1.

Install all removed parts.

2.

Release fuel pressure to 0. Refer to 

ECM-135, "Work Procedure"

.

3.

Set a fuel pressure meter and check fuel pressure. Refer to 

ECM-135, "Work Procedure"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace malfunctioning fuel gauge unit. Refer to  

ECM-135, "Work Procedure"

.

5.

CHECK MASS AIR FLOW SENSOR

WITH CONSULT

+

−

Continuity

A/F sensor 1

ECM

Connector

Terminal

Connector

Terminal

F74

1

F16

64

Existed

2

72

+

Ground

Continuity

A/F sensor 1

Connector

Terminal

F74

1

Ground

Not existed

2

+

Ground

Continuity

ECM

Connector

Terminal

F16

64

Ground

Not existed

72

At idle: 500 kPa (5.0 bar, 5.1 kg/cm

2

, 73 psi)

ECM-238

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

P0172 FUEL INJECTION SYSTEM FUNCTION

1.

Install all removed parts.

2.

Start engine and warm it up to normal operating temperature.

3.

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

*: Check for linear voltage rise in response to increase of engine speed.

WITHOUT CONSULT

1.

Install all removed parts.

2.

Start engine and warm it up to normal operating temperature.

3.

Check the voltage between ECM harness connector terminals under the following conditions.

*: Check for linear voltage rise in response to increase of engine speed.

Is the inspection result normal?

YES

>> GO TO 6.

NO

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

grounds. Refer to 

ECM-180, "Diagnosis Procedure"

.

6.

CHECK FUNCTION OF FUEL INJECTOR

WITH CONSULT

1.

Start engine.

2.

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

3.

Check that each circuit produces a momentary engine speed drop.

WITHOUT CONSULT

1.

Start engine and let it idle.

2.

Listen to each fuel injector operating sound.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Perform trouble diagnosis for fuel injector and circuit,

refer to 

ECM-372, "Diagnosis Procedure"

.

7.

CHECK FUEL INJECTOR

1.

Turn ignition switch OFF.

2.

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

3.

Remove fuel tube assembly. Refer to 

EM-164, "Exploded View"

.

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

4.

The fuel injector harness connectors should remain connected.

5.

Disconnect all ignition coil harness connectors.

Monitor item

Condition

Indication

A/F SEN1 (B1)

Ignition switch ON (Engine stopped.)

Approx. 0.4 V

Idle (Engine is warmed-up to normal op-
erating temperature.)

0.7 - 1.2 V

Idle to about 4,000 rpm

0.7 -1.2 V 

→

 2.4 V*

ECM

Condition

Voltage

Connector

+

–

Terminal

F16

64

72

Ignition switch ON (Engine stopped.)

Approx. 0.4 V

Idle (Engine is warmed-up to normal 
operating temperature.)

0.7 -1.2 V

Idle to about 4,000 rpm

0.7 -1.2 V 

→

 2.4 V*

Clicking sound should 
be heard.

PBIB3332E

P0172 FUEL INJECTION SYSTEM FUNCTION

ECM-239

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

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6.

Prepare pans or saucers under each fuel injector.

7.

Crank engine for about 3 seconds.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace fuel injectors from which fuel does not spray out evenly. Refer to 

EM-164, "Removal and

Installation"

. Always replace O-ring with new ones.

Fuel should be sprayed evenly for each fuel injec-
tor.

ECM-240

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

P0190 FRP SENSOR

P0190 FRP SENSOR

DTC Description

INFOID:0000000010702942

DTC DETECTION LOGIC

POSSIBLE CAUSE

• Harness or connectors (Fuel rail pressure sensor circuit is open or shorted.)
- Fuel rail pressure sensor circuit is open or shorted.
- Sensor power supply 2 is shorted.
• Sensor power supply 2 sensor

FAIL-SAFE

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and let it idle for at least 1 minute.

2.

Check DTC or 1st trip DTC.

Is DTC or 1st trip DTC detected?

YES

>> Proceed to 

ECM-240, "Diagnosis Procedure"

.

NO-1

>> To check malfunction symptom before repair: Refer to 

GI-41, "Intermittent Incident"

.

NO-2

>> Confirmation after repair: INSPECTION END

Diagnosis Procedure

INFOID:0000000010702943

1.

CHECK FRP SENSOR POWER SUPPLY-1

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

P0190

FUEL PRES SEN/CIRC

Signal voltage from the fuel rail pressure sensor remains at more than 4.84 
V/less than 0.2 V for 5 seconds or more.

Engine operating condition in fail-safe mode

Fail safe mode

Vehicle behavior

Traveling con-
trol mode

Accelerator an-
gle variation 
control

ECM controls the accelerator pedal depression speed to make it slower than actual speed. This 
causes a drop in accelerating performance and encourages the driver to repair malfunction.
NOTE:
ECM does not control the accelerator pedal releasing speed.

Combustion 
control mode

Stratified charge 
combustion 
control at start-
ing

No stratified charge combustion at starting (cold start).

Idle speed con-
trol

Stops feedback control of idle speed and controls with specified speed.

Recovery speed 
control at decel-
erating

Stops recovery speed control by the fuel cut at decelerating and controls with specified speed.

Idle neutral con-
trol

Stops idle neutral control.