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Home >> Acura >> 2009 >> TL Base >> Repair and Diagnosis (Single Page) >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Climate Control System >> Climate Control >> Navigation Communication Line Circuit Troubleshooting
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Navigation Communication Line Circuit Troubleshooting

  1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  2. Operate the climate control system in several modes

    Is the climate control system OK? 

    YES  -Go to step 3

    NO  -Do the self-diagnostic function with the HDS (see HOW TO USE THE SELF-DIAGNOSTIC FUNCTION WITH THE HDS ) or the climate control unit (see HOW TO USE THE SELF-DIAGNOSTIC FUNCTION WITHOUT THE HDS )

  3. Go into the SYSTEM DIAGNOSTIC MODE , and select the Self-Diagnosis Mode to check the System Link (see SYSTEM LINKS ).

    Is the A/C or Mic icon red? 

    YES  -

    • If A/C icon is red, go to step 4
    • If Mic icon is red, go to "voice control does not work/respond" in the navigation system symptom troubleshooting (see VOICE CONTROL DOES NOT WORK/RESPOND ).

    NO  -Go to step  10

  4. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
  5. Disconnect audio-navigation unit connector D (20P)
  6. Disconnect climate control unit connector C (20P)
  7. Check for continuity between the following terminals of climate control unit connector C (20P) and audio-navigation unit connector D (20P)

    20P 20P

    No 4 No 4

    No 5 No 5

    No 6 No 14

    Fig 1: Checking Continuity Between Terminals Of Climate Control Unit Connector C (20P) And Audio-Navigation Unit Connector D (20P)
    G05988651Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 8

    NO  -Repair open in the wire(s) between the climate control unit and the audio-navigation unit

  8. Check for continuity between body ground and climate control unit connector terminals No 4,5, and 6 individually
    Fig 2: Checking Continuity Between Body Ground And Climate Control Unit Connector Terminals 4, 5, And 6
    G05988652Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short to body ground in the wire(s) between the climate control unit and the audio-navigation unit

    NO  -Go to step 9

  9. Reconnect climate control unit connector C (20P)
  10. Connect the audio-navigation unit connector D (20P) terminals No 4,5, and 14 with jumper wires
    Fig 3: Connecting Audio-Navigation Unit Connector D (20P) Terminals No 4, 5, And 14 With Jumper Wires
    G05988653Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  12. Press and hold the AUTO button, then press and hold the OFF button
    Fig 4: Identifying Press And Hold AUTO Button
    G05988654Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is the HEAT/VENT indicator solid with the remaining icons blinking? 

    YES  -Do the Unit check with the navigation system (see UNIT CHECK (QUICK CHECK) )

    NO  -Substitute a known-good climate control unit, and recheck If the symptom goes away, replace the original climate control unit (see Climate Control Unit Removal/Installation )

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