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Section 18 (Audio/Video/Navigation (AVN) System): Troubleshooting: Sound

WARNING: This page is about a different car, the 2019 Kia Soul EV. However, it is still accessible from the selected car via links, so may be relevant.
  1. 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. 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. 3. Sound Output_ Noise (H/U_Ext. Amp)
    Inspection Procedure Description
    (1) Duplicate issue
    1. Check H/U Setting (Internal/External amp)
    1. Check H/U Setting (Internal/External amp)
      Fig 1: Checking H/U Setting (Internal/External AMP)
      G12820837Courtesy 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
  4. 3. Sound Output_Noise (External AMP_Cable)
    Inspection Procedure Description
    (2) Inspect H/U/AMP/Cable
    1. AMP (External AMP)
    1. Check AMP (External amp)
      Fig 2: Checking AMP (External AMP)
      G12820838Courtesy 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
    2. Cable (External amp)
    1. Check cable (External amp)
      Fig 3: Checking Cable (External AMP)
      G12820839Courtesy of 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

    G12820839G12820840Courtesy of KIA MOTORS AMERICA, INC.KIA MOTORS AMERICA, INC.
    (2) Check cable connection
    3. Cable connection (Internal/External amp)
    1. Check cable connection to H/U, AMP and mid connector
      Fig 4: Checking Cable Connection (Internal/External AMP)
      G12820841Courtesy of KIA MOTORS AMERICA, INC.

      * Check amp connector (For external amp)

      Fig 5: Checking Mid Connector Present And Find Location At Red Mark
      G12820842Courtesy of KIA MOTORS AMERICA, INC.

      * Check if mid connector is present and find location at the red mark

      Fig 6: Checking Connection Status Of Part ↔ Connector
      G12820843Courtesy of 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, re-connect the cable and re-test

    (2) Check H/U/AMP/Cable
    4. Check for cable defect (Internal/External amp)
    1. Check for cable defect (Internal/external amp)
      Fig 7: Checking Cable Defect (Internal/External AMP; 1 Of 2)
      G12820844Courtesy of KIA MOTORS AMERICA, INC.
      Fig 8: Checking Cable Defect (Internal/External AMP; 2 Of 2)
      G12820845Courtesy of KIA MOTORS AMERICA, INC.
      1. Review cable and connector defect

        (1) Check inside terminal status

      2. Connector pin connection status

        (1) Replace terminal if defect

  5. 4. Sound Output_Noise (H/U_Internal amp spec)
Inspection Procedure Description
(1) Check problem
1. Check H/U settings (Internal/External amp)
  1. Check H/U settings (Internal/External amp)
    Fig 9: Checking H/U Settings (Internal/External AMP)
    G12820846Courtesy of KIA MOTORS AMERICA, INC.
    1. Go to setting -> Sound, check settings for Position, tone
    2. Position, tone center must be set in center.

      → No sound might occur if user changed sound setting ***

    3. Press Center button to reset settings, and check sound
    4. If issue still occurs after above test

      (1) Inspect in order: H/U rear connector → Cable connection → Cable defect

(2) Check H/U/amp/Cable
  1. Check H/U rear connector (Internal amp)
  1. Check H/U defect (Internal amp)
    Fig 10: Checking H/U Rear Connector (Internal AMP)
    G12820847Courtesy of KIA MOTORS AMERICA, INC.
    1. H/U defect review: After disconnecting H/U, increase volume and check speaker output using multi-meter
      1. If voltage increases while increasing volume -> Not H/U issue --> Check cable and connector
        • A1: RL (Rear Left), A2: FL (Front Left), A3: FR (Front Right), A4: RR (Rear Right)
        • Refer to pin location - RL/FL/FR/RR pin location varies
(2) Check cable connection
2. Cable connection (Internal/External amp)
  1. H/U connection status
G12820848Courtesy of KIA MOTORS AMERICA, INC.
*Check H/U connector
  1. Check connection for Part ↔ Connector
  1. Duplicate issue by pulling cable
  2. Check misconnection

    →If issue duplicates, re-connect and check again

(2) Check H/U/Amp/Cable
3. Cable defect (Internal/External amp)
  1. Check cable defect (Internal/external amp)
    Fig 11: Checking Cable Defect (Internal/External AMP; 1 Of 2)
    G12820849Courtesy of KIA MOTORS AMERICA, INC.
    Fig 12: Checking Cable Defect (Internal/External AMP; 2 Of 2)
    G12820850Courtesy of KIA MOTORS AMERICA, INC.
    1. Review cable and connector defect

      (1) Check inside terminal status

    2. Pin connection

      (1) Replace terminal if defect