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Tahoe / Yukon Service Manual

Voice Recognition Malfunction

Cellular, Entertainment, and Navigation | Diagnostic Information and Procedures | Document ID: 5192437 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. DTC Descriptor DTC B1618 Voice Recognition Audio Signal Symptom Byte Information: Symptom Byte List Diagnostic Fault Information

Circuit Circuit Function Short to Ground Open/High Resistance Short to Voltage
5149 Signal B1618 11 B1618 13 —

Circuit/System Description When voice recognition for the infotainment system is started, voice signals from the B24LF Mobile Telephone Microphone – Left Front are passed through the K73 Telematic Control Module to the A11 Radio via the voice recognition audio circuits. Conditions for Running the DTC Vehicle in Service Mode for 5 seconds. Battery voltage must be between 9–16 V. Conditions for Setting the DTC B1618 11 Short to ground on the voice recognition audio signal circuit. Test is run every 250 ms. B1618 13 Open/high resistance on the voice recognition audio signal circuit. Test is run every 250 ms. Conditions for Clearing the DTC The condition responsible for setting the DTC no longer exists. A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred. Diagnostic Aids Refer to the Owners Manual and/or the Navigation System Owners Manual for voice recognition use and commands. When the system recognizes the command the system will either perform the function or ask to confirm the choice by clearly saying “yes” or “no”. If experiencing difficulty with the system recognizing a command, confirm that the command is correct. Background noise such as a climate control fan positioned on high, open windows, or very loud outside noises, can cause voice commands to be misunderstood. Reference Information Schematic Reference Radio/Navigation System Schematics Connector End View Reference Master Electrical Component List 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

  1. Vehicle in service mode, infotainment system on, verify the B24LF Mobile Telephone Microphone – Left Front works correctly. ⇒ If the B24LF Mobile Telephone Microphone – Left Front does not work correctly Refer to Cellular Telephone Microphone Malfunction ⇓ If the B24LF Mobile Telephone Microphone – Left Front works correctly
  1. Begin voice recognition for the infotainment system and clearly speak one of the available commands.
  2. Verify the infotainment system responds correctly to the command. ⇒ If the infotainment system does not respond correctly to the command. 3.1. Clearly speak a different command. 3.2. Verify the infotainment system responds correctly to the command. ⇒ If the infotainment system does not respond correctly to any commands, refer to Circuit/System Testing. ⇓ If the infotainment system responds correctly to the command. 3.3. Refer to the Owners Manual and/or the Navigation System Owners Manual for hints on speaking commands. ⇓ If the infotainment system responds correctly to the command.
  3. All OK Circuit/System Testing
  4. Vehicle off, disconnect harness connector X1 at the K73 Telematic Control Module, vehicle in service mode.
  5. Test for 8-10 V between signal circuit terminal 15 and ground. ⇒ If less than 8 V 2.1. Test circuit 5149 for a short to ground. ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found. 2.2. Test circuit 5149 for an open/high resistance. ⇒ If an open/high resistance is found, repair the fault on the circuit. ⇓ If an open/high resistance is not found. 2.3. Replace the A11 Radio. ⇒ If greater than 10 V 2.1. Test circuit 5149 for a short to voltage. ⇒ If a short to voltage is found, repair the fault on the circuit. ⇓ If a short to voltage is not found. 2.2. Replace the A11 Radio. ⇓ If between 8-11 V
  6. Test the low reference circuit terminal 14 for an open/high resistance in the circuit. ⇒ If an open/high resistance is found repair the fault on the circuit. ⇓ If an open/high resistance is not found. 3.1. Test circuit 5152 for a short to ground. ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found.
  1. Begin voice recognition for the infotainment system and clearly speak one of the available commands.
  2. Verify the infotainment system responds correctly to the command. ⇒ If the infotainment system does not respond correctly to the command 5.1. Clearly speak a different command. 5.2. Verify the infotainment system responds correctly to the command. ⇒ If the infotainment system does not respond correctly to any commands, replace the K73 Telematic Control Module. ⇓ If the infotainment system responds correctly to the command
  3. A fault is currently not present and may be an intermittent condition. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. For control module replacement, programming, and setup refer to: Control Module References