- Symptoms - Cellular Communication

Symptoms - Cellular Communication

Important: The following steps must be completed before using the symptom tables.

1. Perform the Diagnostic System Check - Vehicle, before using the Symptom Tables in order to verify that all of the following are true:

* There are no DTCs set.
* The control module can communicate via the serial data link. Initial Inspection and Diagnostic Overview

2. Review the system operation in order to familiarize yourself with the system functions. Refer to OnStar Description and Operation.

Visual/Physical Inspection

* Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories in Diagnostic Aids. Component Tests and General Diagnostics
* Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

* OnStar One or More Buttons Inoperative
* Unable to Contact OnStar Call Center
* Microphone Inoperative - Caller Cannot Be Heard
* Voice Recognition Inoperative
* OnStar Button LED Inoperative
* No (or Noisy) OnStar Audio
* Global Positioning System (GPS) Data Not Current or Inaccurate