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Home >> Buick >> 2016 >> Envision >> Repair and Diagnosis >> External Pages >> Different car >> Section 180 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> DTC B124C: USB 2 Circuit >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page is about a different car, the 2016 Buick LaCrosse. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify DTC B124C is not set. Since occurrences of this DTC can be caused by an incompatible or faulty USB device, review with the customer the conditions under which their concern occurred.
    • If DTC B124C is set. 

      Refer to Circuit/System testing.

    • If DTC B124C is not set. 
  2. Ignition ON, infotainment system ON.
  3. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.
  4. 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. Insert an SD card with compatible media into the SD card slot.
    2. Verify the media on the SD card can be accessed while operating the system to connect to the SD card.
    • If the SD card reader cannot be accessed, refer to Circuit/System testing.
    • If the SD card reader can be accessed, replace the X83 Auxiliary Audio Input.
    • If audio is heard from the test tool 
  5. Insert an SD card with compatible media into the SD card slot.
  6. Verify the media on the SD card can be accessed while operating the system to connect to the SD card.
    • If the SD card reader media cannot be accessed 

      Refer to Circuit/System testing

    • If the SD card reader media can be accessed 
  7. All OK.
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