CAN communication alarm is an intelligent alarm device developed based on Controller Area Network (CAN) bus technology. By connecting to a CAN network, it receives and parses data frames transmitted by various nodes in real time. Upon detecting preset abnormal conditions—such as fault codes, signal timeouts, or sensor data exceeding limits—it immediately triggers audible, visual, or combined audio-visual alarm outputs, thereby enabling real-time monitoring of system status and the provision of early warnings for anomalies.