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 internal microprocessor integrity conditions within the engine control module (ECM). The hybrid powertrain control module is internal to the drive motor generator power inverter module, and is not serviced separately. The hybrid powertrain control module sends an engine torque requested message to the ECM over the serial data circuits. The ECM monitors the data to verify the indicated engine torque requested calculation is correct. The ECM processor monitors the data to verify that the engine torque command is correct.