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Home >> Nissan-Datsun >> 2003 >> Sentra SE-R, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 2085 (Audio, Visual, Navigation & Telephone System) >> Navigation System >> Self-Diagnosis Mode (DCU) >> Operation Procedure
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Operation Procedure

WARNING: This page is about a different car, the 2007 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. Start the engine.
  2. Turn the audio system off.
  3. While pressing the "4" button, turn the volume control dial clockwise or counterclockwise for 30 clicks or more. (When the self-diagnosis mode is started, a short beep will be heard.)
    Fig 1: Locating 4 Button
    G04909178
  4. The initial trouble diagnosis screen will be shown, and items "Self-Diagnosis (DCU)""Self-Diagnosis (NAVI)""Confirmation/Adjustment" and "CAN DIAG SUPPORT MONITOR" will become selective.
    Fig 2: Self-Diagnosis Screen Display - CAN DIAG SUPPORT MONITOR
    G04909285
  5. Perform self-diagnosis by selecting the "Self-diagnosis".
    • Self-diagnosis subdivision screen will be shown and the operation enters the self-diagnosis mode.
    • A bar graph shown below the self-diagnosis subdivision screen indicates progress of the diagnosis.
      Fig 3: Self-Diagnosis Screen Display - SELF-DIAGNOSIS
      G04914340
  6. When the self-diagnosis completes, optional part confirmation screen will be shown.
    • When connection of an optional part is judged error, a screen to check if the optional part is actually fitted on the vehicle or not will be shown. When fitted, select the switch of the part on the screen and press "End". Then the "SELF DIAGNOSIS" screen will be shown.
    • When the optional part is connected normally, the switch for the part will not appear on the screen.
      Fig 4: Self-Diagnosis Screen Display - SELF DIAGNOSIS
      G04904242
  7. On the "SELF DIAGNOSIS" screen, each unit name will be colored according to the diagnosis result, as follows.

    Green : Not malfunctioning. 

    Yellow : Cannot be judged by self-diagnosis results. 

    Red : Unit is malfunctioning. 

    Gray : Diagnosis has not been done. 

  8. If several malfunctions are present in a unit, color of its switch on the screen will be either red, yellow, or gray, determined by the malfunction of the highest priority.
    Fig 5: Self-Diagnosis Screen Display - SELF DIAGNOSIS
    G04909288
  9. Select a switch on the "SELF DIAGNOSIS" screen and comments for the diagnosis results will be shown.
    • When the switch is green, the following comment will be shown. "Self-diagnosis did not detect any error. Please refer to the "CONFIRMATION/ADJUSTMENT " function or service manual for more detailed diagnosis information."
    • When the switch is yellow, the following comment will be shown. "Connection to the following unit is abnormal. See the service manual for further details".
    • When the switch is red, the following comment will be shown. "DCU is abnormal".
      Fig 6: Self-Diagnosis Screen Display - SELF DIAGNOSIS
      G04909289