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Home >> Cadillac >> 2015 >> XTS Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Entertainment Systems >> Cellular System, Entertainment System, And Navigation System >> Diagnostic Information and Procedures >> Auxiliary Audio Input Malfunction >> Circuit/System Testing
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Circuit/System Testing

Auxiliary Audio Input Jack

  1. Ignition OFF, disconnect the X1 harness connector at the X83 Auxiliary Audio Input. Ignition ON, infotainment system ON.
  2. Test for 2.5-3.5 V between the signal circuit terminal 5 and ground.
    • If less than 2.5 V 
    1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the A11 Radio.
    • If greater than 3.5 V 
    1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio, ignition ON.
    2. Test for less than 1 V between the detection circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the A11 Radio.
    • If between 2.5-3.5 V 
  3. Test for less than 1 V between the signal circuits listed below and ground:
    • Left auxiliary audio signal circuit terminal 1
    • Right auxiliary audio signal circuit terminal 2
    • Auxiliary audio common signal circuit terminal 3
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio. Ignition ON.
    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 A11 Radio.
    • If less than 1 V 
  4. Ignition OFF, disconnect the X1 harness connector at the A11 Radio.
  5. Test for infinite resistance between the signal circuits listed below and ground:
    • Auxiliary audio common signal circuit terminal 8
    • Left auxiliary audio signal circuit terminal 9
    • Right auxiliary audio signal circuit terminal 10
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  6. Test for less than 5 Ω between the signal circuit terminals listed below:
    • A11 Radio signal circuit terminal 9 X1 and the X83 Auxiliary Audio Input signal circuit terminal 1 X1
    • A11 Radio signal circuit terminal 10 X1 and the X83 Auxiliary Audio Input signal circuit terminal 2 X1
    • A11 Radio signal circuit terminal 8 X1 and the X83 Auxiliary Audio Input signal circuit terminal 3 X1
    • If 5 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 5 Ω 
  7. Replace the X83 Auxiliary Audio Input. Connect all harness connectors.
  8. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input 3.5 mm (1/8 in.) input jack and select the AUX test mode.
  9. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
    • If audio is not heard from the test tool 

      Replace the A11 Radio.

    • If audio is heard from the test tool 
  10. All OK.

USB Port and SD Card Reader

  1. Ignition OFF, disconnect the X1 harness connector at the X83 Auxiliary Audio Input.
  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.
    • 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.
    • If the test lamp illuminates 
  4. Verify the USB cable is properly connected at all components and in-line connections, 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.

    • If no connection problems or cable damage is noted. 
  5. Connect the X1 harness connector at the X83 Auxiliary Audio Input.
  6. Disconnect the vehicle USB cable X3 harness connector at the K74 Human Machine Interface Control Module and the X83 Auxiliary Audio Input.
  7. Connect the EL-50034-14 Infotainment Test Cable and the EL-50334-2 Type-A Female to Mini-B Male Cable together. Connect the assembled test cable to the K74 Human Machine Interface Control Module and the X83 Auxiliary Audio Input.
  8. Ignition ON, infotainment system ON.
  9. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.
  10. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
    • If audio is not heard from the test tool 
    1. Replace the X83 Auxiliary Audio Input. Connect all harness connectors.
    2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input 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 infotainment system while operating the system to play audio from the test tool.
      • If audio is not heard from the test tool, replace the K74 Human Machine Interface Control Module.
      • If audio is heard from the test tool.
    4. All OK.
    • If audio is heard from the test tool 
  11. Connect the vehicle USB cable X3 harness connector at the K74 Human Machine Interface Control Module.
  12. Disconnect the console to I/P USB in-line connector. Connect the assembled test cable to the I/P side of the in-line USB cable connector and the X83 Auxiliary Audio Input.
  13. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.
  14. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
    • If audio is not heard from the test tool 

      Replace the I/P USB cable assembly.

    • If audio is heard from the test tool 
  15. Replace the console USB cable assembly.

USB Receptacle

  1. Verify the USB cable is properly connected at the X4 harness connector at the K74 Human Machine Interface Control Module.
    • If connection problems or cable damage is noted. 

      Perform the appropriate repair or replacement to correct any issues.

    • If no connection problems or cable damage is noted. 
  2. Disconnect the vehicle USB cable X4 harness connector at the K74 Human Machine Interface Control Module.
  3. Connect the EL-50334-2 Type-A Female to Mini-B Male Cable to the K74 Human Machine Interface Control Module.
  4. Ignition ON, infotainment system ON.
  5. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the EL-50334-2 Type-A Female to Mini-B Male Cable and select the USB test mode.
  6. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
    • If audio is not heard from the test tool 

      Replace the K74 Human Machine Interface Control Module.

    • If audio is heard from the test tool 
  7. Replace the USB cable assembly.
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