Keyword 2000 Circuit Description
WARNING: This page is about a different car, the 2008 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
The keyword protocols utilize a single wire bi-directional data line between the module and the scan tool. The message structure is a request and response arrangement. The keyword serial data line is used for scan tool diagnostics of the climate control seat module (CCSM) only. Other modules on the vehicle do not exchange data on this circuit.