Diagnosis Procedure

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM-ENGINE CONTROL SYSTEM- ".

1. CHECK GROUND CONNECTION
   1. Turn ignition switch OFF.
   2. Check ground connection E9. Refer to Ground Inspection in "CIRCUIT INSPECTION ".

      Is the inspection result normal? 

      YES: GO TO 2.

      NO: Repair or replace ground connection.

2. CHECK EXHAUST VALVE TIMING (EVT) CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT-I
   1. Disconnect EVT control position sensor harness connector.
   2. Turn ignition switch ON.
   3. Check the voltage between EVT control position sensor harness connector and ground.

      DTC	EVT control position sensor			Ground	Voltage (V)
      	Bank	Connector	Terminal
      P1078	1	F43	1	Ground	Approx. 5
      P1084	2	F42	1

      Is the inspection result normal? 

      YES: GO TO 3.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

3. CHECK EVT CONTROL POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
   1. Turn ignition switch OFF.
   2. Disconnect ECM harness connector.
   3. Check the continuity between EVT control position sensor harness connector and ECM harness connector.

      DTC	EVT control position sensor			ECM		Continuity
      	Bank	Connector	Terminal	Connector	Terminal
      P1078	1	F43	2	F13	64	Existed
      P1084	2	F42	2		68

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

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

4. CHECK EVT CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
   1. Check the continuity between EVT control position sensor harness connector and ECM harness connector.

      DTC	EVT control position sensor			ECM		Continuity
      	Bank	Connector	Terminal	Connector	Terminal
      P1078	1	F43	3	F13	66	Existed
      P1084	2	F42	3		71

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

      Is the inspection result normal? 

      YES: GO TO 5.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

5. CHECK EVT CONTROL POSITION SENSOR

   Refer to "COMPONENT INSPECTION ".

   Is the inspection result normal? 

   YES: GO TO 6.

   NO: Replace malfunctioning EVT control position sensor. Refer to "EXPLODED VIEW ".

6. CHECK CAMSHAFT (EXH)

   Check the following.

   • Accumulation of debris to the signal plate of camshaft rear end
   • Chipping signal plate of camshaft rear end

     Is the inspection result normal? 

     YES: GO TO 7.

     NO: Remove debris and clean the signal plate of camshaft rear end or replace camshaft. Refer to CAMSHAFT .

     Fig 1: Checking Chipping Signal Plate Of Camshaft Rear End Visually

     Courtesy of NISSAN NORTH AMERICA, INC.
7. CHECK INTERMITTENT INCIDENT

   Refer to "INTERMITTENT INCIDENT ".

   : INSPECTION END