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Home >> Nissan-Datsun >> 2004 >> Sentra Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - QG18DE >> DTC P1278: A/F Sensor 1 >> DTC Confirmation Procedure
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DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.
NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

TESTING CONDITION: 

Before performing the following procedure, confirm that battery voltage is more than 11V at idle. 

With CONSULT-II 

  1. Perform IDLE AIR VOLUME LEARNING . Make sure that "CMPLT" is displayed on CONSULT-II screen. If "INCMP" is displayed, follow the instruction for Idle Air Volume Learning.
  2. Select "A/F SEN1 (B1) P1278/P1279" of "A/F SEN1" in "DTC WORK SUPPORT" mode.
  3. Touch "START".
  4. When the following conditions are met, "TESTING" will be displayed on the CONSULT-II screen.
    Fig 1: Testing Conditions Chart
    G00773190Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 2: Displaying A/F SEN1 (B1) P1278/P1279 Mode (1 Of 3)
    G00773191Courtesy of NISSAN MOTOR CO., U.S.A.

    If "TESTING" is not displayed after 20 seconds, retry from step   2 . 

  5. Following the instructions of CONSULT-II screen, set D position with "OD" OFF (A/T) or 3rd position (M/T) and release accelerator pedal fully.
    Fig 3: Displaying A/F SEN1 (B1) P1278/P1279 Mode (2 Of 3)
    G00773192Courtesy of NISSAN MOTOR CO., U.S.A.
  6. Make sure that "TESTING" changes to "COMPLETED".

    If "TESTING" changed to "OUT OF CONDITION", retry from step 6. 

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

    If NG is displayed, go to DIAGNOSTIC PROCEDURE .

    Fig 4: Displaying A/F SEN1 (B1) P1278/P1279 Mode (3 Of 3)
    G00773193Courtesy of NISSAN MOTOR CO., U.S.A.