Circuit/System Description

WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The drive motor generator battery is cooled by a drive motor battery vent fan motor. The battery vent fan motor and battery vent fan relay are located inside the drive motor generator battery assembly. B+ to the battery vent fan is provided from the battery vent fan relay when the drive motor generator battery control module (GBCM) supplies a ground to the battery vent fan relay. A grounding wire from the battery vent fan motor assembly completes the path to case ground. A 5 V circuit is provided from the battery vent fan motor assembly, to the GBCM. The GBCM uses a pulse width modulated (PWM) signal on the 5 V circuit to control the battery vent fan motor duty cycle. The battery vent fan motor also supplies an additional 5 V signal that indicates vent fan speed back to the GBCM, the lower the voltage the greater the fan speed. The GBCM uses 4 battery temperature sensors, one air inlet duct and one air outlet temperature sensor to control battery vent fan motor operation and speed.