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.

The drive motor generator battery assembly has an air inlet and air outlet temperature sensors. The air inlet and air outlet temperature sensors are located on the inlet and outlet air ducts of the hybrid battery vent fan. The air inlet temperature sensor is referred to as sensor 1 and the air outlet temperature sensor is referred to as sensor 2. The air temperature sensors are a variable resistor that measures the temperature of the inlet and outlet air. The control module supplies 5 volts to the signal circuit and a ground for the low reference circuit. The air inlet and outlet temperature sensor resistance changes with temperature. The lower the temperature, the higher the resistance of the sensor. The higher the temperature, the lower the resistance of the sensor. The BECM uses the air inlet and outlet temperature sensors to determine if air is circulating through the drive motor generator battery assembly.