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Home >> Chevrolet >> 2021 >> Traverse Premier, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 47 (Cellular, Entertainment, And Navigation System) >> Diagnostic Information and Procedures >> DTC B1A91 >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2020 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.

FTB 11, 12, 13, 2B

    NOTE:

    More than one speaker may be connected to each signal circuit in a parallel configuration. Make sure to disconnect all speakers on the signal circuit.

  1. Ignition OFF, disconnect the appropriate P19 Speaker (s):
    • DTC B1A91 = P19 Speaker (s) connected to circuit 1860
  2. Ignition ON, infotainment system ON, mute OFF.
  3. Test for 5-7 V between the signal circuit terminal 2 and ground.
    • If less than 5 V 
    1. Test the appropriate circuit for a short to ground:
      • DTC B1A91 = Circuit 1860
      • If a short to ground is found, repair the circuit fault.
      • Go to next step: If a short to ground is not found
    2. Test the appropriate circuit for an open/high resistance:
      • DTC B1A91 = Circuit 1860
      • If an open/high resistance is found, repair the circuit fault.
      • Go to next step: If an open/high resistance is not found
    3. Replace the T3 Audio Amplifier
    • If greater than 7 V 
    1. Test the appropriate circuit for a short to voltage:
      • DTC B1A91 = Circuit 1860
      • If a short to voltage is found, repair the circuit fault.
      • Go to next step: If a short to voltage is not found
    2. Replace the T3 Audio Amplifier
    • Go to next step: If between 5-7 V 
  4. Test for 5-7 V between the signal circuit terminal 1 and ground.
    • If less than 5 V 
    1. Test the appropriate circuit for a short to ground:
      • DTC B1A91 = Circuit 1960
      • If a short to ground is found, repair the circuit fault.
      • Go to next step: If a short to ground is not found
    2. Test the appropriate circuit for an open/high resistance:
      • DTC B1A91 = Circuit 1960
      • If an open/high resistance is found, repair the circuit fault.
      • Go to next step: If an open/high resistance is not found
    3. Replace the T3 Audio Amplifier
    • If greater than 7 V 
    1. Test the appropriate circuit for a short to voltage:
      • DTC B1A91 = Circuit 1960
      • If a short to voltage is found, repair the circuit fault.
      • Go to next step: If a short to voltage is not found
    2. Replace the T3 Audio Amplifier
    • Go to next step: If between 5-7 V 
  5. Disconnect the appropriate harness connector at the T3 Audio Amplifier
  6. Test for infinite resistance between signal circuit terminal 1 and signal circuit terminal 2 at the appropriate P19 Speaker.
    • If less than infinite resistance 

      Repair the short between the two signal circuits.

    • Go to next step: If infinite resistance 
  7. Replace the appropriate P19 Speaker.

FTB 28

  1. Ignition ON/Vehicle in Service Mode. Infotainment system ON, mute OFF.
  2. Verify that none of the DTCs listed below are set:
    • DTC B1A91 2B
    • If the DTC is set 
    1. Clear the DTC.
    2. Infotainment system ON, mute OFF.
    3. Verify the DTC does not reset.
      • If the DTC resets, replace the T3 Audio Amplifier
      • Go to next step: If the DTC does not reset
    4. All OK.
    • Go to next step: If the DTC is not set 
  3. All OK.
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