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Circuit/System Testing

USB/ HDMI Port

  1. Ignition OFF, disconnect the X1 harness connector at the X82 Audio/Video Input Adapter.
  2. Test for less than 10 Ω between the ground circuit terminal 4 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 Ω 
  3. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF, remove the test lamp.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
    • Go to next step: If the test lamp illuminates 
  4. Verify the USB and LVDS cables are properly connected at the X82 Audio/Video Input Adapter, A33 Media Disc Player and the console to I/P in-line connector, and there is no damage to the cable or connections.
    • If connection problems or cable damage is noted. 

      Perform the appropriate repair or replacement to correct any issues.

    • Go to next step: If no connection problems or cable damage is noted. 
  5. Replace the X82 Audio/Video Input Adapter. Connect all harness connectors.
  6. Ignition On/Vehicle in Service Mode. Rear seat entertainment system ON.
  7. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X82 Audio/Video Input Adapter USB port and select the USB test mode.
  8. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the rear seat entertainment system while operating the system to play audio from the test tool.
    • If audio is not heard from the test tool 
    1. Replace the A33 Media Disc Player.
    2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X82 Audio/Video Input Adapter USB port and select the USB test mode.
    3. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the rear seat entertainment system while operating the system to play audio from the test tool.
      • If audio is not heard from the test tool, replace the USB cable connected to the X82 Audio/Video Input Adapter. Verify audio is heard from the test tool. If audio is not heard from the test tool, replace the USB cable connected to the A33 Media Disc Player.
      • Go to next step: If audio is heard from the test tool.

        Go to next step: All OK.

    • Go to next step: If audio is heard from the test tool 
    1. Connect a compatible device to the X82 Audio/Video Input Adapter HDMI port. Operate the rear seat entertainment system to connect to the HDMI port as the source.
    2. Verify that audio and video from the device can be accessed while operating the device.
      • If audio/video can not be accessed from the device, replace the LVDS cable connected to the X82 Audio/Video Input Adapter. Verify audio/video can be accessed from the device. If audio/video cannot be accessed from the device, replace the A33 Media Disc Player.
      • Go to next step: If audio/video can be accessed from the device.

        Go to next step: All OK.

  9. All OK

Wired Headphone Jack

  1. Ignition OFF, disconnect the X1 harness connector at the X82 Audio/Video Input Adapter. Ignition On/Vehicle in Service Mode. Infotainment system ON.
  2. Test for less than 1 V between the signal circuits listed below and ground:
    • Left audio headphone signal circuit terminal 1
    • Right audio headphone signal circuit terminal 2
    • Audio common headphone signal circuit terminal 3
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X2 harness connector at the A33 Media Disc Player. Ignition On/Vehicle in Service Mode.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the A33 Media Disc Player.
    • Go to next step: If less than 1 V 
  3. Ignition OFF, disconnect the X2 harness connector at the A33 Media Disc Player.
  4. Test for infinite resistance between the signal circuits listed below and ground:
    • Left audio headphone signal circuit terminal 1
    • Right audio headphone signal circuit terminal 2
    • Audio common headphone signal circuit terminal 3
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  5. Test for less than 5 Ω between the signal circuit terminals listed below:
    • A33 Media Disc Player signal circuit terminal 1 X2 and the X82 Audio/Video Input Adapter signal circuit terminal 1 X1
    • A33 Media Disc Player signal circuit terminal 2 X2 and the X82 Audio/Video Input Adapter signal circuit terminal 2 X1
    • A33 Media Disc Player signal circuit terminal 3 X2 and the X82 Audio/Video Input Adapter signal circuit terminal 3 X1
    • If 5 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 5 Ω 
  6. Replace the X82 Audio/Video Input Adapter. Connect all harness connectors.
  7. Connect a wired headphone to the X82 Audio/Video Input Adapter headphone jack. Operate the rear seat entertainment system to connect an available audio source to the wired headphone jack.
  8. Verify that audio from the source can be heard with the wired headphones, adjusting the rotary volume control as necessary.
    • If the audio cannot be heard 

      Test or replace the A33 Media Disc Player.

    • Go to next step: If the audio can be heard 
  9. All OK.
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