Circuit/System Description

WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.

The drive motor generator battery control module is also referred to as the battery energy control module (BECM). The BECM will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the BECM to the hybrid powertrain control module (HPCM) through the Hybrid LAN communication circuit. The HPCM is the host controller for diagnostic trouble code (DTC) information.

This diagnostic applies to internal microprocessor integrity conditions within the BECM. This is an internal electronic fault detection diagnostic of the BECM. This fault is internal to the BECM and no external circuits are involved. Failure of these diagnostics can cause erratic hybrid drive motor battery and HV contactor relay operation.