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Home >> Cadillac >> 2019 >> XTS Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 53 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> DTC B124B >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page is about a different car, the 2018 Cadillac XTS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify DTC B124B 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 B124B is set. 

      Refer to Circuit/System testing.

    • Go to next step: If DTC B124B is not set. 
  2. Ignition ON, infotainment system ON.
  3. Connect a compatible USB device to the USB port and attempt to play audio from a comparable know good vehicle.
  4. Verify audio is heard through the infotainment system while operating the USB device.
    • If audio is not heard 

      USB device is not compatible, try a different USB device.

    • Go to next step: If audio is heard 
  5. Connect a compatible USB device to the USB port and attempt to play audio from the customers vehicle.
  6. Verify audio is heard through the infotainment system while operating the USB device.
    • If audio is not heard 

      Refer to Circuit/System Testing

    • Go to next step: If audio is heard 

      Go to next step: All OK

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