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Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Infotainment >> Cellular System, Entertainment System And Navigation System - Diagnostic Information And Procedures >> Diagnostic Information and Procedures >> Voice Recognition Malfunction (IO6 with UE1) >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF, disconnect the X1 harness connector at the K74 Human Machine Interface Control Module.
  2. Disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module. Ignition On/Vehicle in Service Mode.
  3. Test for less than 1 V between the signal circuit terminal listed below and ground.
    • Voice recognition audio signal terminal 6
    • Voice recognition audio low reference terminal 12
    • If 1 V greater 

      Repair the short to voltage on the circuit.

    • If less than 1 V 
  4. Ignition OFF.
  5. Test for infinite resistance between the signal circuits listed below and ground:
    • Voice recognition audio signal terminal 6
    • Voice recognition audio low reference terminal 12
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  6. Test for less than 5 Ω between the terminals listed below:
    • K74 Human Machine Interface Control Module signal circuit terminal 1 X1 and the K73 Telematics Communication Interface Control Module signal circuit terminal 6 X2
    • K74 Human Machine Interface Control Module low reference circuit terminal 2 X1 and the K73 Telematics Communication Interface Control Module low reference circuit terminal 12 X2
    • If 5 Ω greater 

      Repair the open/high resistance in the circuit.

    • If less than 5 Ω 
  7. Replace the K74 Human Machine Interface Control Module. Connect all harness connectors.
  8. Begin voice recognition for the infotainment system and clearly speak one of the available commands.
    NOTE: Refer to the Owners Manual and/or the Navigation System Owners Manual for voice recognition use and commands.
  9. Verify the infotainment system responds correctly to the command.
    • If the infotainment system does not respond correctly to the command 
    1. Clearly speak a different command.
    2. Verify the infotainment system responds correctly to the command.
      • If the infotainment system does not respond correctly to any commands, replace the K73 Telematics Communication Interface Control Module.
    • If the infotainment system responds correctly to the command 
  10. All OK