Conditions for Setting the DTC

WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The EBCM diagnoses a fault condition in the master cylinder pressure sensor, and sends a serial data message to the TBCM.
The EBCM diagnoses a fault condition in the wheel speed sensors, and sends a serial data message to the TBCM.
The TBCM losses communication with the EBCM.