Body Control Module (BCM)

/ Command Central for a Host of Essential Functions

Automotive body control modules are crucial in connecting and managing several systems and functions within the vehicle. 

Inputs from digital and analog inputs are fed into the microcontroller unit (MCU). They are then processed and the appropriate outputs are directed to the load motor and lighting control to execute the desired functions. BCMs are often connected to other key systems within the vehicle, including the instrument cluster. 

Efficient, reliable communication and switching must occur in real time for safe operation, so the BCM’s design should include protections for ESD, overvoltage, and reverse battery charges.

/ Application Considerations

There are many key decisions that impact the quality and reliability of the body control module. Design engineers should carefully weigh the following:

• Safety - reliable components made to withstand a host of harsh conditions are essential for driver and passenger safety
• Processing speed & response times - fast switching of the inputs and processing of how to direct the outputs for several systems must take place in real time  
• Reverse battery protection - protective components are needed to prevent damaging reverse polarity in the battery
• Overvoltage protection - safety measures to handle transients and power surges should be incorporated into the design
• Efficiency - minimizing energy losses and maximizing energy efficiency are important in all automotive systems, including the BCM
• ESD protection - electrostatic discharge can harm BCM performance and should be planned for in the design
• Applicable industry standards - all components must adhere to strict automotive industry guidelines, including AEC-Q101