Infiniti FX35, FX50 (S51). Manual - part 858

P100A, P100B VVEL SYSTEM

EC-973

< DTC/CIRCUIT DIAGNOSIS >

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YES

>> GO TO 9.

NO

>> INSPECTION END

9.

CHECK VVEL ACTUATOR SUB ASSEMBLY

Refer to 

EC-973, "Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)"

.

Is the inspection result normal?

YES

>> GO TO 11.

NO

>> GO TO 10.

10.

REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.

Replace VVEL actuator sub assembly.

2.

Perform 

EC-974, "Special Repair Requirement"

.

>> INSPECTION END

11.

CHECK VVEL LADDER ASSEMBLY

Refer to 

EM-236, "Inspection"

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Is the inspection result normal?

YES

>> GO TO 13.

NO

>> GO TO 12.

12.

REPLACE CYLINDER HEAD, VVEL LADDER ASSEMBLY AND VVEL ACTUATOR SUB ASSEMBLY

1.

Replace cylinder head, VVEL ladder assembly and VVEL actuator sub assembly.

2.

Perform 

EC-974, "Special Repair Requirement"

.

>> INSPECTION END

13.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

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>> INSPECTION END

Component Inspection (VVEL ACTUATOR MOTOR)

INFOID:0000000005237446

1.

CHECK VVEL ACTUATOR MOTOR

1.

Turn ignition switch OFF.

2.

Disconnect VVEL actuator motor harness connector.

3.

Check resistance between VVEL actuator motor terminals as per the following.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.

Replace VVEL actuator sub assembly.

2.

Perform 

EC-974, "Special Repair Requirement"

.

>> INSPECTION END

Component Inspection (VVEL ACTUATOR SUB ASSEMBLY)

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1.

CHECK VVEL ACTUATOR SUB ASSEMBLY

1.

Turn ignition switch OFF.

VVEL actuator motor

Resistance

Terminal

1 and 2

16 

Ω

 or less

EC-974

< DTC/CIRCUIT DIAGNOSIS >

[VK50VE]

P100A, P100B VVEL SYSTEM

2.

Remove VVEL actuator sub assembly. Refer to 

EM-228, "Disassembly and Assembly"

.

3.

Turn the ball screw shaft to check that it works smoothly.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

REPLACE VVEL ACTUATOR SUB ASSEMBLY

1.

Replace VVEL actuator sub assembly.

2.

Perform 

EC-974, "Special Repair Requirement"

.

>> INSPECTION END

Special Repair Requirement

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1.

PERFORM VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT

Refer to 

EC-583, "VVEL CONTROL SHAFT POSITION SENSOR ADJUSTMENT : Special Repair Require-

ment"

.

>> GO TO 2.

2.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-582, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

.

>> END

P1078, P1084 EVT CONTROL POSITION SENSOR

EC-975

< DTC/CIRCUIT DIAGNOSIS >

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P1078, P1084 EVT CONTROL POSITION SENSOR

Description

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Exhaust valve timing control position sensor detects the protrution of
the signal plate installed to the exhaust camshaft front end. 
This sensor signal is used for sensing a position of the exhaust cam-
shaft.
This sensor uses a Hall IC.
Based on the position of the exhaust camshaft, ECM controls
exhaust valve timing control solenoid valve to optimize the shut/open
timing of exhaust valve for the driving condition.

DTC Logic

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DTC DETECTION LOGIC

NOTE:
If DTC P1078 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to

EC-965, "DTC Logic"

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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.

>> GO TO 2.

JMBIA0064ZZ

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1078

Exhaust valve timing 
control position sensor 
(bank 1) circuit

An excessively high or low 
voltage from the sensor is 
sent to ECM.

• Harness or connectors

[Exhaust valve timing control position sensor (bank 1) cir-
cuit is open or shorted)
(Accelerator pedal position sensor 2 circuit is shorted.)
(Battery current sensor circuit is shorted.)
[Camshaft position sensor (bank 1) circuit is shorted.]
(Crankshaft position sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is shorted.)
(Manifold absolute pressure sensor circuit is shorted.)

• Exhaust valve timing control position sensor
• Accelerator pedal position sensor
• Battery current sensor
• Camshaft position sensor (bank 1)
• Crankshaft position sensor
• EVAP control system pressure sensor
• Manifold absolute pressure sensor
• Accumulation of debris to the signal pick-up portion of the 

camshaft

P1084

Exhaust valve timing 
control position sensor 
(bank 2) circuit

• Harness or connectors

[Exhaust valve timing control position sensor (bank 2) cir-
cuit is open or shorted)

• Exhaust valve timing control position sensor (bank 2)
• Crankshaft position sensor
• Camshaft position sensor (bank 2)
• Accumulation of debris to the signal pick-up portion of the 

camshaft

EC-976

< DTC/CIRCUIT DIAGNOSIS >

[VK50VE]

P1078, P1084 EVT CONTROL POSITION SENSOR

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and let it idle for 10 seconds.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-976, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

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1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection M95, F33, F34. Refer to Ground Inspection in 

GI-39, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT-I

1.

Disconnect exhaust valve timing (EVT) control position sensor harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between exhaust valve timing control position sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 8.

NO-1

>> P1078: GO TO 3.

NO-2

>> P1084: Repair open circuit, short to ground or short to power in harness or connectors.

3.

CHECK EVT CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT-II

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check the continuity between EVT control position sensor harness connector and ECM harness connec-
tor.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair open circuit.

4.

CHECK SENSOR POWER SUPPLY CIRCUIT

Check harness for short to power and short to ground, between the following terminals.

DTC

EVT control position sensor

Ground

Voltage (V)

Bank

Connector

Terminal

P1078

1

F59

1

Ground

Approx. 5

P1084

2

F63

1

EVT control position sensor

ECM

Continuity

Bank

Connector

Terminal

Connector

Terminal

1

F59

1

F111

91

Existed