Circuit/System Description
WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
This diagnostic applies to communication integrity conditions between the engine control module (ECM) and the hybrid powertrain control module. The hybrid powertrain control module monitors a state of health message that the ECM transmits to verify the ECM is functioning properly. The hybrid powertrain control module is part the drive motor power inverter module and is not serviced separately.