Initial Inspection and Diagnostic Overview

1. Determine type of audio complaint.
2. Make sure that the customer does not have an aftermarket mobile electronic component, such as a cellular telephone, that has been removed before the vehicle was left for service. This is extremely important, because that component may be emitting the frequency(s) that is (are) causing the complaint.
3. OnStar equipment directly affects the audio system. It is designed to use the vehicle speakers for incoming communications. The audio system, OnStar system, or both, may be contributing to the audio complaint. Refer to the information. and the OnStar system.
4. Try to duplicate condition (listen to AM or FM. start vehicle, put in a good CD or cassette, test switches, etc.).
^ Refer to the "Hardware Symptom Table" for the appropriate diagnostic procedure(s) for hardware related failures or performance complaints.
^ Refer to the "Noise and Reception Symptom Table" for the appropriate diagnostic procedure(s) for noise or reception complaints. Symptom Table - Noise and Reception Performance Complaints