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Home >> Infiniti >> 2004 >> QX56 RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P1278, P1288: A/F Sensor 1 >> DTC Confirmation Procedure >> With Consult-II
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With Consult-II

  1. Start engine and warm it up to normal operating temperature.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Start engine and keep the engine speed between 3,500 and 4,000 RPM for at least 1 minute under no load.
  4. Let engine idle for 1 minute.
  5. Select "A/F SEN1(B1) P1278/P1279" or "A/F SEN1(B1) P1288/P1289" of "A/F SEN1" in "DTC WORK SUPPORT" mode with CONSULT-II.
  6. Touch "START".

    If "COMPLETED" appears on CONSULT-II screen, go to step  10.

    If "COMPLETED" does not appear on CONSULT-II screen, go to the next step.

    Fig 1: Selecting "A/F SEN1(B1) P1278/P1279" Or "A/F SEN1(B1) P1288/P1289" Of "A/F SEN1" In "DTC WORK SUPPORT" Mode With CONSULT-II.
    G02691748Courtesy of NISSAN MOTOR CO., U.S.A.
  7. After perform the following procedure, 'TESTING" will be displayed on the CONSULT-II screen.
    1. Increase the engine speed up to 4,000 to 5,000 RPM and keep it for 10 seconds.
    2. Fully release accelerator pedal and then let engine idle for about 10 seconds.

      If "TESTING" is not displayed after 10 seconds, refer to  TROUBLE DIAGNOSIS - SPECIFICATION VALUE  . 

  8. Wait for about 20 seconds at idle at under the condition that "TESTING" is displayed on the CONSULT-II screen.
    Fig 2: Identifying "TESTING" Screen Display
    G02691749Courtesy of NISSAN MOTOR CO., U.S.A.
  9. Make sure that "TESTING" changes to "COMPLETED"

    If "TESTING" changed to "OUT OF CONDITION", refer to  TROUBLE DIAGNOSIS - SPECIFICATION VALUE  . 

  10. Make sure that "OK" is displayed after touching "SELF-DIAG RESULT".

    If "NG" is displayed, go to DIAGNOSTIC PROCEDURE .

    Fig 3: Identifying "COMPLETED" Screen Display
    G02691750Courtesy of NISSAN MOTOR CO., U.S.A.