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Diagnostic Procedure

  1. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I 
    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 51 and ground under the following conditions.
    Fig 1: Checking Voltage At ECM
    G00787560Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 2: ECM Voltage Specifications
    G00787561Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: GO TO  3 3.
  2. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II 

    Check voltage between ECM terminal 51 and ground under the following conditions. See Fig 1

    Fig 3: ECM Voltage Specifications
    G00787563Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: GO TO  7 .
  3. CHECK REAR WINDOW DEFOGGER FUNCTION 
    1. Start engine.
    2. Turn ON the rear window defogger switch.
    3. Check the rear windshield. Is the rear windshield heated up?

    Yes or No 

    1. Yes: GO TO 4.
    2. No: Refer to REAR WINDOW DEFOGGER .
  4. CHECK REAR WINDOW DEFOGGER INPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect rear window defogger relay.
    4. Check harness continuity between ECM terminal 51 and rear window defogger relay terminal 5 and 7.
      Fig 4: Checking Harness Continuity Between ECM and Rear Window Defogger Relay
      G00787564Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  6 .
    2. NG: GO TO 5.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B1, M5
    • Harness connectors M229, F66
    • Diode M35
    • Harness for open and short between ECM and rear window defogger relay
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  6. CHECK INTERMITTENT INCIDENT 

    Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. : INSPECTION END 
  7. CHECK HEADLAMP FUNCTION 
    1. Start engine.
    2. Turn the lighting switch ON at 1st position with high beam.
    3. Check that headlamps are illuminated.

    OK or NG 

    1. OK: GO TO 8.
    2. NG: Refer to HEADLAMP (FOR U.S.A.) or HEADLAMP (FOR CANADA) DAYTIME LIGHT SYSTEM .
  8. CHECK HEADLAMP INPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect headlamp RH relay (Models for USA), daytime light control unit harness connector (Models for Canada).
    4. Check harness continuity between ECM terminal 51 and headlamp LH relay terminal 7 under the following conditions.

      (Models for USA)

      Fig 5: Checking Harness Continuity Between ECM And Headlamp LH Relay
      G00787565Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Check harness continuity between ECM terminal 51 and daytime light control unit terminal 7 under the following conditions. (Model for Canada)
      Fig 6: Checking Harness Continuity Between ECM And Daytime Light Control Unit
      G00787566Courtesy of NISSAN MOTOR CO., U.S.A.
    6. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  10 .
    2. NG: GO TO 9.
  9. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E81, M15
    • Harness connectors M229, F66
    • Diode E79
    • Harness for open and short between ECM and headlamp RH relay or daytime light control unit
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  10. CHECK INTERMITTENT INCIDENT 

    Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT, TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. : INSPECTION END 
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