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Diagnostic Test

INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for scheduled maintenance.
2. Open engine hood and check the following:
  
  Fig 1: Checking Harness Connectors For Improper Connections
  Courtesy of NISSAN NORTH AMERICA, INC.
  - Harness connectors for improper connections
  - Wiring harness for improper connections, pinches and cut
  - Vacuum hoses for splits, kinks and improper connections
  - Hoses and ducts for leaks
  - Air cleaner clogging
  - Gasket
3. Confirm that electrical or mechanical loads are not applied.
  - Headlamp switch is OFF.
  - Air conditioner switch is OFF.
  - Rear window defogger switch is OFF.
  - Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
  
  Fig 2: Engine Coolant Temperature
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  Ensure engine stays below 1, 000 RPM.
5. Run engine at about 2, 000 RPM for about 2 minutes under no load.
  
  Fig 3: Engine RPM
  Courtesy of NISSAN NORTH AMERICA, INC.
6. Make sure that no DTC is displayed with CONSULT or GST.
Is any DTC detected?

YES

GO TO STEP 2 .

NO

GO TO STEP 3 .

REPAIR OR REPLACE

Repair or replace components as necessary according to corresponding Diagnostic Procedure.

GO TO STEP 3 .

CHECK TARGET IDLE SPEED
1. Run engine at about 2, 000 RPM for about 2 minutes under no load.
2. Rev engine (2, 000 to 3, 000 RPM) two or three times under no load, then run engine at idle speed for about 1 minute.
  
  Fig 4: Checking Target Idle Speed
  Courtesy of NISSAN NORTH AMERICA, INC.
3. Check idle speed.
  For procedure, refer to INSPECTION .
  
  For specification, refer to IDLE SPEED .
Is the inspection result normal?

YES

GO TO STEP 10 .

NO

GO TO STEP 4 .

PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform DESCRIPTION .
GO TO STEP 5 .

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform DESCRIPTION .

GO TO STEP 6 .

PERFORM IDLE AIR VOLUME LEARNING

Perform DESCRIPTION .

Is Idle Air Volume Learning carried out successfully?

YES

GO TO STEP 7 .

NO

Follow the instruction of Idle Air Volume Learning. Then GO TO STEP 4 .

CHECK TARGET IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
  For procedure, refer to INSPECTION .
  
  For specification, refer to IDLE SPEED .
Is the inspection result normal?

YES

GO TO STEP 10 .

NO

GO TO STEP 8 .

DETECT MALFUNCTIONING PART

Check the Following.
- Check camshaft position sensor (PHASE) and circuit. Refer to DTC LOGIC .
- Check crankshaft position sensor (POS) and circuit. Refer to DTC LOGIC .
Is the inspection result normal?

YES

GO TO STEP 9 .

NO

Repair or replace. Then GO TO STEP 4

CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but this is a rare case.)
2. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to DESCRIPTION for the one with INTELLIGENT KEY SYSTEM, or DESCRIPTION for the one without INTELLIGENT KEY SYSTEM.
GO TO STEP 4 .

CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light.
  
  Fig 5: Timing Indicator
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  For procedure, refer to INSPECTION
  
  For specification, refer to IGNITION TIMING .
  
  1 : Timing indicator
Is the inspection result normal?

YES

INSPECTION END.

NO

GO TO STEP 11 .

PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform WORK PROCEDURE .
GO TO STEP 12 .

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform WORK PROCEDURE .

GO TO STEP 13 .

PERFORM IDLE AIR VOLUME LEARNING

Perform WORK PROCEDURE .

Is Idle Air Volume Learning carried out successfully?

YES

GO TO STEP 14 .

NO

Follow the instruction of Idle Air Volume Learning. Then GO TO STEP 4 .

CHECK TARGET IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
  For procedure, refer to INSPECTION .
  
  For specification, refer to IDLE SPEED .
Is the inspection result normal?

YES

GO TO STEP 15 .

NO

GO TO STEP 17 .

CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
  
  Fig 6: Timing Indicator
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  For procedure, refer to INSPECTION .
  
  For specification, refer to IGNITION TIMING .
  
  1 : Timing indicator
Is the inspection result normal?

YES

INSPECTION END.

NO

GO TO STEP 16 .

CHECK TIMING CHAIN INSTALLATION

Check timing chain installation. Refer to INSPECTION .

Is the inspection result normal?

YES

GO TO STEP 17 .

NO

Repair the timing chain installation. Then GO TO STEP 4 .

DETECT MALFUNCTIONING PART

Check the following.
- Check camshaft position sensor (PHASE) and circuit. Refer to DTC LOGIC .
- Check crankshaft position sensor (POS) and circuit. Refer to DTC LOGIC .
Is the inspection result normal?

YES

GO TO STEP 18 .

NO

Repair or replace. Then GO TO STEP 4

CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but this is a rare case.)
2. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to DESCRIPTION for the one with INTELLIGENT KEY SYSTEM, or DESCRIPTION for the one without INTELLIGENT KEY SYSTEM.
GO TO STEP 4 .