B2CF054 - B2CF054 Dynamic Control Fault

meaning the controller cannot maintain preset longitudinal speed follow-up logic or safe distance keeping logic. This fault is usually associated with the status monitoring of key execution components and is a preliminary signal for the system entering a protective failure strategy.

Common Fault Symptoms

When the vehicle detects B2CF054 Dynamic Control Fault and satisfies set storage conditions, drivers will face the following perceptible instrument feedback and experience changes during driving:

• Adaptive Cruise Control Function Completely Disabled: The ACC indicator light on the dashboard extinguishes or displays a specific fault icon (such as an exclamation mark); the system cannot perform speed setting or vehicle-following functions.
• Speed Control Intervention Failure: Even if the driver sets a target speed, the system will not automatically accelerate or decelerate according to road conditions, switching to manual full control mode.
• Radar Signal Source Status Abnormal Indicator: The central control screen or dashboard displays "Front Radar Fault", "Sensor Unavailable" or similar warning messages, indicating that the system has lost perception capability.
• System Exits Driver Assistance State: The originally enabled auxiliary driving interface automatically closes, and may be accompanied by an audible alarm sound reminding the driver to take over vehicle control.

Core Fault Cause Analysis

Based on the definition of B2CF054 and its preconditions, the core causes of this fault can be analyzed from three dimensions: hardware components, physical connections, and control unit logic:

• Hardware Components (Front Millimeter Wave Radar): As the source of the perception system, if the internal circuit of the front millimeter wave radar itself is damaged, transmission/reception modules malfunction, or critical calibration data is lost, effective distance and speed feedback signals cannot be output. This is the main physical trigger for "Dynamic Control Fault".
• Lines and Connectors (Physical Connections): The communication bus (such as CAN bus) connecting the Adaptive Cruise Controller and the Millimeter Wave Radar has high impedance, poor grounding, or unstable power supply, causing signal attenuation or bit errors during transmission, making it impossible for the controller to receive real-time data.
• Controller (Logical Operation and Judgment): Although hardware input is normal, if the processor inside the ACC control unit responsible for dynamic control algorithm logic makes logical operation errors, or fails to evaluate sensor data confidence threshold levels under specific operating conditions, it actively determines a "Dynamic Control Fault" and records this DTC.

Technical Monitoring and Trigger Logic

The controller's self-check logic imposes strict limitations on system dynamic characteristics after startup to ensure the accuracy of fault determination. The specific trigger mechanism is as follows:

• Monitoring Target Parameters: The controller focuses on monitoring power supply voltage stability and the initialization completion status after radar signal power-up, ensuring that sensors have working conditions within a safe voltage range.
• Voltage Monitoring Range: Only when the system supply voltage is stable within the $9V$~$16V$ interval will dynamic control logic be activated and enter the fault determination process; if outside this range, the system will ignore or terminate the monitoring status to prevent false reports.
• Time Window Logic: Fault determination is not instantaneous but starts evaluation after 3s (3 seconds) following vehicle power-on initialization sequence completion. This ensures radar hardware has sufficient time for self-check and data calibration.
• Operation Mode Limitations: The conditions to trigger this fault require the system to be in a non-debug state, i.e., Factory mode disabled. Only under normal mass-production vehicle operation mode (i.e., not engineering diagnostic mode) will the controller determine this fault and illuminate the dashboard warning light.

Cause Analysis Based on the definition of B2CF054 and its preconditions, the core causes of this fault can be analyzed from three dimensions: hardware components, physical connections, and control unit logic:

• Hardware Components (Front Millimeter Wave Radar): As the source of the perception system, if the internal circuit of the front millimeter wave radar itself is damaged, transmission/reception modules malfunction, or critical calibration data is lost, effective distance and speed feedback signals cannot be output. This is the main physical trigger for "Dynamic Control Fault".
• Lines and Connectors (Physical Connections): The communication bus (such as CAN bus) connecting the Adaptive Cruise Controller and the Millimeter Wave Radar has high impedance, poor grounding, or unstable power supply, causing signal attenuation or bit errors during transmission, making it impossible for the controller to receive real-time data.
• Controller (Logical Operation and Judgment): Although hardware input is normal, if the processor inside the ACC control unit responsible for dynamic control algorithm logic makes logical operation errors, or fails to evaluate sensor data confidence threshold levels under specific operating conditions, it actively determines a "Dynamic Control Fault" and records this DTC.

Technical Monitoring and Trigger Logic

The controller's self-check logic imposes strict limitations on system dynamic characteristics after startup to ensure the accuracy of fault determination. The specific trigger mechanism is as follows:

• Monitoring Target Parameters: The controller focuses on monitoring power supply voltage stability and the initialization completion status after radar signal power-up, ensuring that sensors have working conditions within a safe voltage range.
• Voltage Monitoring Range: Only when the system supply voltage is stable within the $9V$~$16V$ interval will dynamic control logic be activated and enter the fault determination process; if outside this range, the system will ignore or terminate the monitoring status to prevent false reports.
• Time Window Logic: Fault determination is not instantaneous but starts evaluation after 3s (3 seconds) following vehicle power-on initialization sequence completion. This ensures radar hardware has sufficient time for self-check and data calibration.
• Operation Mode Limitations: The conditions to trigger this fault require the system to be in a non-debug state, i.e., Factory mode disabled. Only under normal mass-production vehicle operation mode (i.e., not engineering diagnostic mode) will the controller determine this fault and illuminate the dashboard warning light.