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Circuit/System Testing

WARNING: This page is about a different car, the 2018 Buick Envision. However, it is still accessible from the selected car via links, so may be relevant.

Microphone Malfunction

  1. Ignition OFF, disconnect the harness connector at the B24 Cellular Phone Microphone, ignition ON.
  2. Test for 8.0-10.5 V between the signal circuit terminal B and ground.
    • If less than 8.0 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • Go to next step: 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 vehicle K73 Telematics Communication Interface Control Module.
    • If greater than 10.5 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, 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.
      • Go to next step: If less than 1 V, replace the K73 Telematics Communication Interface Control Module.
    • Go to next step: If between 8.0-10.5 V 
  3. Test for less than 1 V between the signal circuit terminal A and ground.
    • If greater than 1 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, 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 in the circuit.
      • If less than 1 V, repair the K73 Telematics Communication Interface Control Module.
    • Go to next step: If less than 1 V 
  4. Test for greater than 8 V between the signal circuit terminal B and the signal circuit terminal A.
    • If less than 8 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • Go to next step: 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 vehicle K73 Telematics Communication Interface Control Module.
    • Go to next step: If greater than 9 V 
  5. Test or replace the B24 Cellular Phone Microphone.
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