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Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK STOP LAMP SWITCH CIRCUIT 
    1. Turn ignition switch OFF.
    2. Check the stop lamp when depressing and releasing the brake pedal.
      STOP LAMP CONDITION

      Brake Pedal Stop lamp
      Fully released Not illuminated
      Slightly depressed Illuminated

    OK or NG 

    1. OK: GO TO  4
    2. NG: GO TO  2.
  2. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Disconnect stop lamp switch harness connector.
      Fig 1: Locating Stop Lamp Switch
      G02334105Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Check voltage between stop lamp switch terminal 3 and ground with CONSULT-II or tester.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  4
    2. NG: GO TO  3.
    Fig 2: Checking Voltage Between Stop Lamp Switch Terminal 3 & Ground
    G02334106Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • 10A fuse
    • Fuse block (J/B) connector E101
    • Harness for open and short between stop lamp switch and fuse
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Disconnect stop lamp switch harness connector.
    3. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4.

      Refer to Wiring Diagram.

      1. Continuity should exist  .
    4. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  6
    2. NG: GO TO  5.
    Fig 3: Checking Stop Lamp Switch Input Signal Circuit For Open & Short
    G02334107Courtesy of NISSAN MOTOR CO., U.S.A.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M15
    • Harness connectors M72, F102
    • Harness for open or short between ECM and stop lamp switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  6. CHECK STOP LAMP SWITCH 

    Refer to Component Inspection .

    OK or NG 

    1. OK: GO TO  7.
    2. NG: Replace stop lamp switch.
  7. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    1. INSPECTION END 
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