Circuit/System Description

The battery energy control module (BECM) dedicated bus is a communication bus used to communicate between the BECM and the hybrid battery interface control modules inside the hybrid battery pack assembly. The BECM dedicated bus does not communicate with the scan tool.

This diagnostic is used to check the internal BECM dedicated bus off. If the transmit error counter of a bus is greater than 255 (carry condition in case of an 8-bit transmit error counter) then the supervisor requests the physical layer to set the bus into the "Bus Off" state. At this time, the battery energy control module increases its fail count. When this fail count is over X Cal Value (7) during Y Cal Value(10 samples), this fail code will happen.