GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2008 🢒 DTS 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 Navigation System - Voice Recognition Inoperative

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provide an overview of each diagnostic category.

Circuit/System Description

With UE1

The vehicle navigation radio and communication interface module (Onstar® system) both utilize the cellular microphone to receive voice commands. The cellular microphone is connected directly to the communication interface module. The navigation radio receives voice signals from the communication interface module via dedicated voice recognition circuits.

Without UE1

The navigation radio is connected directly to the cellular microphone to receive voice commands.

Reference Information

Schematic Reference

    •  OnStar Schematics
    •  Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Navigation System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, verify the OnStar® voice recognition is operating normally.

⇒If the OnStar® voice recognition is inoperative, refer to OnStar Microphone Inoperative - Caller Cannot Be Heard.
⇒If the OnStar® voice recognition operates normally, or the vehicle is not equipped with OnStar® , refer to Circuit/System testing.

Circuit/System Testing

With UE1

  1. Ignition OFF, disconnect the X3 harness connector at the communication interface module.
  2. Ignition ON, test for 9.5-10.5 volts between the voice recognition signal circuit terminal 2 and ground.
    3. ⇒If less than specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
    ⇒If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  3. Test for 9.5-10.5 volts between the voice recognition signal circuit terminal 2 and the voice recognition low reference circuit terminal 4.
    4. ⇒If less than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the radio.
  4. If all circuits test normal, replace the communication interface module.

Without UE1

  1. Ignition OFF, disconnect the harness connector at the cellular microphone.
  2. Ignition ON, test for 9.5-10.5 volts between the signal circuit terminal B and ground.
    3. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
    ⇒If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
  3. Test for test for 9.5-10.5 volts between the signal circuit terminal B and the drain circuit terminal A.
    4. ⇒If less than the specified range, test the drain circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the radio.
  4. If all circuits test normal, replace the cellular microphone.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Mobile Telephone Microphone Replacement
    •  Control Module References for radio and communication interface module replacement, setup, and programming