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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 to 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 and registration of all NATS ignition key IDs. Refer to DESCRIPTION (with intelligent key) or DESCRIPTION (without intelligent key).
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 .
  - Timing indicator (1)
Is the inspection result normal?

YES

GO TO STEP 19 .

NO

GO TO STEP 11 .

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

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform DESCRIPTION .

GO TO STEP 13 .

PERFORM IDLE AIR VOLUME LEARNING

Perform DESCRIPTION .

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 .
  - Timing indicator (1)
Is the inspection result normal?

YES

GO TO STEP 19 .

NO

GO TO STEP 16 .

CHECK TIMING CHAIN INSTALLATION

Check timing chain installation. Refer to REMOVAL AND INSTALLATION .

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 (with intelligent key). DESCRIPTION (without intelligent key).
GO TO STEP 4 .

INSPECTION END

If ECM is replaced during this BASIC INSPECTION procedure, perform DESCRIPTION .

INSPECTION END