@chu @Betterifyouneil @BobLefridge @greg I think the bus your friend is referring to is CAN bus. It's used in ALL modern cars, ICE, hybrid or EVs. Basically, if your car has automatic door locks, it most probably uses CAN bus. It's been a standard in the industry for decades now. And no, a fail in a CAN bus node doesn't bring the whole system down. CAN bus is fault-tolerant, and you should really do an awful implementation to allow a non-critical node to bring the system down.