Symptoms - Cellular Communication: Notes
WARNING: This page is about a different car, the 2016 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
The following steps must be completed before using the symptom table.
- 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 modules 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 (with EF7 or Z49) and OnStar Description and Operation (without EF7 or Z49) .