Circuit/System Verification

2016 GMC Sierra 3500 HD SLE, 4D Cab Chassis, 6.6L Eng VIN 8, 4WDSECTION Circuit/System Verification
  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.

    • If DTC B124B 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 

      Refer to Circuit/System Testing

    • If audio is heard from test tool 
  5. Verify the infotainment system can be switched to AUX as the audio source with the EL-50334-20 Multi-Media Interface Tester (MIT) connected to the auxiliary audio input jack.
    • If the infotainment system can not be switched to AUX as the audio source 

      Refer to Circuit/System Testing

    • If the infotainment system can be switched to AUX as the audio source 
  6. Verify the audio from the EL-50334-20 Multi-Meida Interface Tester (MIT) is heard through the vehicle infotainment system while operating the test tool to begin audio playback.
    • If audio is not heard from the test tool. 

      Refer to Circuit/System Testing

    • If audio is heard from the test tool. 
  7. All OK
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.