CAN bus

The modules in the satellite use two CAN Bus networks to communicate with each other without the use of a host computer.

CANalyzer has been continually updated since then, and today it is considered the world's leading analysis tool for CAN buses.

The PID query and response occurs on the vehicle's CAN Bus.

This is competing with the CAN Bus proposal from Japan (including CHAdeMO) and China (separate DC connector proposal) and notably none of their car manufacturers has signed up to the Combined Charging System so far.

Not all these layers are necessary, e.g. a vehicle might implement a native CAN Bus interface to USB or Bluetooth, without using the OBD socket or the reference OpenXC Vehicle interface Module.

This protocol allows it to skip integrated circuit electronics as they are required for other charging protocols like the CAN Bus used with Chademo or EnergyBus - the SAE J1772 is considered robust enough for a range of 40 C to +85 C.