2018 Kia Optima Plug-In Hybrid EXFACTORY OEM SERVICE PROCEDURE

Section 59 (Audio/Video/Navigation (AVN) System (PHEV)): Troubleshooting: Sound

WARNING: This page is about a different car, the 2017 Kia Optima. However, it is still accessible from the selected car via links, so may be relevant.
  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
    (2) Duplicate issue
    1. Check H/U Setting (Internal/External amp)
    		  
    1. Check H/U Setting (Internal/External amp)
    G12351017Courtesy of KIA MOTORS AMERICA, INC.
    1. Setting → Sound - Check position, tone settings
    2. Set position, tone to 'center'.

      →User may have changed settings to mute speakers

    3. Reset setting by pressing center button, then check sound
  1. Sound Output_Noise (External AMP_Cable)
    Inspection Procedure Description
    (2) Inspect H/U/AMP/Cable
    1. AMP (External AMP)
    		  
    1. Check AMP (External amp)
    G12351018Courtesy of KIA MOTORS AMERICA, INC.
    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)
    (2) Inspect H/U/AMP/Cable
    • Cable (External amp)
    		  
    1. Check cable (External amp)
    G12351019G12351020Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    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

    →Issue occurs (=Open) -> Cable wiring issue
    G12351019G12351020Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    (2) Check cable connection
    • Cable connection (Internal/External amp)
    1. Check cable connection to H/U, AMP and mid connector
    G12351021G12351022G12351023Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    * Check amp connector (For external amp)
    G12351021G12351022G12351023Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    * Check if mid connector is present and find location at the red mark
    G12351021G12351022G12351023Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    * Check H/U connector
    1. Check connection status of Part ↔ Connector
      1. Check noise by pulling cable a little
      2. Check for incorrect cable mounting
    →If issue continues, reconnect the cable and retest
    (2) Check H/U/AMP/Cable
    • Check for cable defect (Internal/External amp)
    1. Check for cable defect (Internal/external amp)
    G12351024G12351025Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
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