GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 CTS 🢒 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

The vehicle navigation radio and Onstar® system both utilize the cellular microphone to receive voice commands. The navigation radio receives an audio voice signal from the communication interface module (CIM).

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Radio/Audio 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.

Circuit/System Testing
  1. Ignition OFF, disconnect the X3 harness connector at the CIM.
  2. Ignition ON, test for 8.5-9.5 volts between the navigation voice 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. Ignition ON, test for less than 1 volt between the navigation voice low reference circuit terminal 4 ground.
    4. ⇒If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the radio.
  4. Ignition OFF, test for less than 10 ohms between the navigation voice low reference circuit terminal 4 and ground.
    5. ⇒If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the radio.
  5. Ignition ON, test for 8.5-9.5 volts between the navigation voice signal circuit terminal 2 and the drain wire circuit terminal 5.
    6. ⇒If less than specified range, test the drain wire circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the radio.
  6. Ignition OFF, disconnect the X4 harness connector at the radio.
  7. Test for infinite resistance between ground and the navigation voice low reference circuit terminal 16.
    8. ⇒If less than the specified value, test the low reference circuit for a short to ground.
  8. If all circuits test normal, replace the CIM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for Radio and CIM replacement, setup, and programming