2019 Kia Optima EXFACTORY OEM SERVICE PROCEDURE

Section 235 (Audio/Video/Navigation (AVN) System (PHEV)): Troubleshooting: Sound

WARNING: This page is about a different variant/trim than selected.
  1. Features/Misdiagnose cases
    Inspection Description
    (1) System features
    1. Ignition ON (H/U → B+, ACC Power on), H/U Power ON → Sound for Radio, Media, Navigation, Voice Guidance.
    2. External amp is attached at the trunk. External amp communicates with H/U via CAN (Control Area Network)

      (* External amp location may vary)
    (2) Misdiagnose cases
    1. Mute or irregular sound might occur if customer have changed sound settings (position, tone, bass, middle, treble)

      (This is normal, yet misdiagnosed)

    2. Poor sound quality if low-quality soundtrack is played

      (Example: Application like I-MEPS will provide poor sound quality. Customers using BT stream to play I-MEPS claims H/U replacement for low sound quality)
  2. Sound output - Common
    Inspection Description
    (1) Vehicle modification
    1. Check vehicle modification (Front Panel, Black box, Mic, Taxi meter, etc.)
    (2) Duplicate issue
    1. Check sound/noise output
    2. Check H/U settings
    (3) Check H/U/Amp/Cable
    1. Check defect of 1) H/U, 2) amp, 3) connector defect in order (Ext. amp spec)
    2. Check defect of 1) H/U, 2) connector (For Internal amp)
    (4) Defect caused by Ext. parts N/A
    (5) Check part defect
    1. Check defect by replacing H/U
  3. Sound Output_ Noise (H/U_Ext. Amp)
    Inspection Procedure Description
    (1) Duplicate issue
    1. Check H/U Setting

      (Internal/External amp)
    G13157674Courtesy of KIA MOTORS AMERICA, INC.

    1. Check H/U Setting (Internal/External amp)
      1. Setting → Sound - Check position, tone settings
      2. Set position, tone to 'center".
        1. →User may have changed settings to mute speakers
      3. Reset setting by pressing center button, then check sound
    1. 3. Sound Output_Noise (External AMP_Cable)
      Inspection Procedure Description
      G13157675Courtesy of KIA MOTORS AMERICA, INC.

      (2) Inspect H/U/AMP/Cable
      1. AMP
      (External AMP)
      1. Check AMP (External amp)
        1. Review defect
          1. Check amp battery and ACC voltage (9V - 16V) → Vehicle issue if unable to read voltage
          2. Check audio output → Amp issue if no audio output - Check speaker impedance → If not normal, check wire/cable, speaker (disconnect the cable and test)
      G13157676Courtesy of KIA MOTORS AMERICA, INC.

      (2) Inspect H/U/AMP/Cable
      2. Cable
      (External amp)
      1. Check cable (External amp)
        1. AMP ↔ H/U Line inspection
          1. MMCAN +/-: Check open/short using multi-meter
          2. SPDIF +/-: Check open/short using multi-meter
          3. NAVI +/-: Check open/short using multi-meter
            1. →Issue occurs (=Open) -> Cable wiring issue
      G13157677Courtesy of KIA MOTORS AMERICA, INC.
      (2) Check cable connection
      3. Cable connection
      (Internal/External amp)
      G13157678G13157679G13157680Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
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