Nissan Sentra. Manual - part 372

EC-184

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

P0078 EVT CONTROL SOLENOID VALVE

4. Also check harness for short to ground.
Is the inspection result normal?

YES

>> Perform the trouble diagnosis for power supply circuit.

NO

>> Repair or replace error-detected parts.

3.

CHECK EXHAUST VALVE TIMING CONTROL SOLENOID VALVE GROUND CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between EVT control solenoid valve harness connector and ECM harness connec-

tor.

4. Also check harness for short to ground and to power. 
Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK EXHAUST VALVE TIMING CONTROL SOLENOID VALVE

Check the exhaust valve timing control solenoid valve. Refer to 

EC-181, "Component Inspection (IVT Control

Solenoid Valve)"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-39, "Intermittent Incident"

.

NO

>> Replace exhaust valve timing control solenoid valve. Refer to 

EM-49, "Removal and Installation"

.

Component Inspection (EVT Control Solenoid Valve)

INFOID:0000000009758445

1.

CHECK EXHAUST VALVE TIMING CONTROL SOLENOID VALVE-1

1. Turn ignition switch OFF.

2. Disconnect exhaust valve timing control solenoid valve harness connector.

3. Check resistance between exhaust valve timing control solenoid valve terminals as per the following.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace exhaust valve timing control solenoid valve. Refer to 

EM-49, "Removal and Installation"

.

2.

CHECK EXHAUST VALVE TIMING CONTROL SOLENOID VALVE-2

1. Remove exhaust valve timing control solenoid valve. Refer to 

EM-48, "Exploded View"

.

+

+

Continuity

EVT control solenoid valve

IPDM E/R

Connector

Terminal

Connector

Terminal

F55

1

E45

26

Existed

+

+

Continuity

EVT control solenoid valve

ECM

Connector

Terminal

Connector

Terminal

F55

2

F25

94

Existed

Exhaust valve timing control 

solenoid valve

Resistance

+

−

Terminal

1

 2

7.0 - 7.8 

Ω [at 20°C (68°F)]

1

Ground

∞ Ω

(Continuity should not exist)

2

P0078 EVT CONTROL SOLENOID VALVE

EC-185

< DTC/CIRCUIT DIAGNOSIS >

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2. Provide 12 V DC between exhaust valve timing control solenoid

valve terminals 1 and 2, and then interrupt it. Check that the

plunger moves as shown in the figure.

CAUTION:

Do not apply 12 V DC continuously for 5 seconds or more.

Doing so may result in damage to the coil in exhaust valve

timing control solenoid valve.

NOTE:

Always replace O-ring when exhaust valve timing control

solenoid valve is removed.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace exhaust valve timing control solenoid valve. Refer to 

EM-49, "Removal and Installation"

.

JMBIA0079ZZ

EC-186

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

P0101, P0102, P0103 MAF SENSOR

P0101, P0102, P0103 MAF SENSOR

DTC Logic

INFOID:0000000009758446

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting 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.
Which DTC is detected?

P0102 >> GO TO 2.

P0101 or P0103>>GO TO 3.

2.

PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0102

1. Start engine and wait at least 5 seconds.

2. Check DTC.
Is DTC detected?

YES

>> Proceed to 

EC-187, "Diagnosis Procedure"

.

NO

>> INSPECTION END

3.

PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0101 AND P0103-1

1. Turn ignition switch ON and wait at least 5 seconds.

2. Check DTC.
Is DTC detected?

YES

>> Proceed to 

EC-187, "Diagnosis Procedure"

.

NO

>> GO TO 4.

4.

PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0101 AND P0103-2

1. Start engine and wait at least 5 seconds.

2. Check DTC.
Is DTC detected?

YES

>> Proceed to 

EC-187, "Diagnosis Procedure"

.

NO

>> INSPECTION END

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P0101

MAF SEN/CIRCUIT-B1
(Mass or volume air flow “A” 
circuit range/performance)

An excessively high voltage from the mass air 
flow sensor is sent to ECM.

• Harness or connectors

(Mass air flow sensor circuit is open or 
shorted.)

• Mass air flow sensor
• Sensor power supply 2 circuit

P0102

MAF SEN/CIRCUIT-B1
(Mass or volume air flow “A” 
circuit low input)

An excessively low voltage from the mass air 
flow sensor is sent to ECM.

• Harness or connectors

(Mass air flow sensor circuit is open or 
shorted.)

• Intake air leaks
• Mass air flow sensor
• Sensor power supply 2 circuit

P0103

MAF SEN/CIRCUIT-B1
(Mass or volume air flow “A” 
circuit high input)

An excessively high voltage from the mass air 
flow sensor is sent to ECM.

• Harness or connectors

(Mass air flow sensor circuit is open or 
shorted.)

• Mass air flow sensor
• Sensor power supply 2 circuit

P0101, P0102, P0103 MAF SENSOR

EC-187

< DTC/CIRCUIT DIAGNOSIS >

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Diagnosis Procedure

INFOID:0000000009758447

1.

INSPECTION START

Confirm the detected DTC.
Which DTC is detected?

P0102 >> GO TO 2.

P0101 and P0103>>GO TO 3.

2.

CHECK INTAKE SYSTEM

Check the following for connection.

• Air duct

• Vacuum hoses

• Intake air passage between air duct to intake manifold
Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Reconnect or replace error-detected parts.

3.

CHECK MASS AIR FLOW (MAF) SENSOR POWER SUPPLY

1. Turn ignition switch OFF.

2. Disconnect MAF sensor harness connector.

3. Turn ignition switch ON.

4. Check the voltage between MAF sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 7.

4.

CHECK MAF SENSOR GROUND CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between MAF sensor harness connector and ECM harness connector.

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

YES

>> GO TO 5.

NO

>> Repair or replace error-detected parts.

5.

CHECK MAF SENSOR INPUT SIGNAL CIRCUIT

1. Check the continuity between MAF sensor harness connector and ECM harness connector.

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

+

−

Voltage

(Approx.)

MAF sensor

Connector

Terminal

F31

1

Ground

5 V

+

−

Continuity

MAF sensor

ECM

Connector

Terminal

Connector

Terminal

F31

2

F24

34

Existed

+

−

Continuity

MAF sensor

ECM

Connector

Terminal

Connector

Terminal

F31

3

F24

35

Existed