Symptoms - Cellular Communication: Notes
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
The following steps must be completed before using the symptom tables.
- Perform the Diagnostic System Check - Vehicle
. Before using the Symptom Tables, verify that all of the following are true:
- There are no DTCs set.
- The control module can communicate via the serial data link.
- Review the system operation in order to familiarize yourself with the system functions. Refer to OnStar Description and Operation .
- Perform the OnStar Symptom Diagnosis . This symptom table will enable the user to verify the customer complaint and narrow it to its source.