A Controller Area Network (CAN) controller for a plurality of electronic devices electrically connected to form a control circuit in a CAN system, includes a controller and a circuit configuring device. The controller is electrically connected with the electronic devices to form two circuit terminals of the control circuit. The circuit configuring device is electrically connected with the controller in such a manner that when the electrical disconnection occurs in the CAN system, the circuit configuring device will re-configure the control circuit for switching the two circuit terminals at the electrical disconnection of the respective electronic device to by-pass the electrical disconnection from the control circuit, such that the circuit configuring device is electrically re-connected to the two circuit terminals for completing the control circuit in a closed manner so as to keep the electronic devices functioning in the CAN system.