B1B4D00 - Rear Right Center Sensor After-shock Time Fault
B1B4D00 Rear Right Center Sensor Ring Time Fault - Technical Documentation
### H3 Fault Depth Definition
Fault Code Identifier (DTC Code): B1B4D00
System Name: Parking Assist System
Specific Definition: This fault code indicates a "Ring Time" logical anomaly in the rear right center radar sensor within a specific operating cycle. In the automotive active safety and parking assist architecture, the control unit must monitor the timing of pulse signal feedback from the sensors in real time. "Ring Time" in this context refers to the deviation between the expected signal duration of continuous system response after the sensor receives an echo or triggers an event and the actual physical detection time value. This fault indicates that the control unit (Controller) failed to validate the instantaneous signal stability of the sensor through preset threshold logic, causing a logical interruption in the detection capability for obstacles in specific directions, directly affecting the accurate calculation of parking distance and blind spot monitoring functions.
### H3 Common Fault Symptoms
When DTC B1B4D00 is detected and the system enters a restricted mode, vehicle owners may observe the following specific phenomena in driving experience:
- Dashboard Indicator Anomaly: The parking assist warning light on the dashboard may illuminate, or specific icons related to "Radar Sensor Fault" may flash.
- Restricted Function Alerts: In the parking guidance interface of the central control screen, distance data for the rear right center area is missing, shows as dashed lines, or fixed values, and no longer updates dynamically with vehicle speed and obstacle changes.
- Audio Warning Failure: When approaching obstacles at low speeds, sound alarms for that specific area may be completely silent or significantly reduced in volume.
- System Status Feedback: The vehicle diagnostic system records a status marker "Partial Parking Assist System Function Loss", indicating the need to inspect hardware connections or controller logic.
### H3 Core Fault Cause Analysis
Based on technical principles and raw data classification, the core causes of this fault can be investigated by checking the following three key dimensions:
-
Hardware Component Failure (Sensor)
Primarily Rear Right Center Radar Sensor Failure. As the terminal execution unit for emitting and receiving ultrasonic signals, if the internal oscillation circuit or demodulation module of the sensor is physically damaged, it causes delays in echo signal processing, leading the system to determine that the "Ring Time" does not meet standard characteristics. -
Wiring/Connector Abnormality (Wiring & Connector)
Involves Harness or Connector Faults. This includes issues at the physical connection level, such as excessive contact resistance in the power and ground lines from the sensor to the control unit, pin corrosion, short circuits, or open circuits. These lead to distortion of pulse signals transmitted to the controller, triggering timing logic errors. -
Controller Logic Operation Anomaly (Controller)
Primarily points to Left Domain Controller Failure. The domain controller is responsible for data fusion and logical judgment from radar sensors. If threshold parameters stored inside it are lost, calculation modules compute incorrectly, or communication buses are disturbed, the controller may falsely mark Ring Time timeout even if the sensor is normal.
### H3 Technical Monitoring & Trigger Logic
The determination of this fault code follows strict electronic electrical architecture logic, with the specific monitoring process as follows:
-
Monitoring Target (Monitoring Target):
The system continuously collects signal voltage fluctuation characteristics and pulse duration of the rear right center sensor. It focuses on monitoring whether the attenuation curve of the signal after a specific trigger complies with preset physical models. -
Numerical Range & Logic (Numerical Range & Logic):
Based on current input data, fault determination does not rely on specific analog voltage thresholds (e.g., $9V$~$16V$), but is based on Time Logic. The system records the signal residual duration in the sensor trigger state; if it exceeds the controller's allowed logic window, it determines an abnormality. -
Specific Operating Condition:
This fault is activated and stored only when the vehicle enters an electrical active state. The specific trigger condition is: Ignition switch placed in "ON" position. Once the ignition switch is open and the initialization self-check process is completed, if the above sensor timing parameters are found non-compliant, the system will immediately write the B1B4D00 fault code to record the current state.
Cause Analysis Based on technical principles and raw data classification, the core causes of this fault can be investigated by checking the following three key dimensions:
- Hardware Component Failure (Sensor) Primarily Rear Right Center Radar Sensor Failure. As the terminal execution unit for emitting and receiving ultrasonic signals, if the internal oscillation circuit or demodulation module of the sensor is physically damaged, it causes delays in echo signal processing, leading the system to determine that the "Ring Time" does not meet standard characteristics.
- Wiring/Connector Abnormality (Wiring & Connector) Involves Harness or Connector Faults. This includes issues at the physical connection level, such as excessive contact resistance in the power and ground lines from the sensor to the control unit, pin corrosion, short circuits, or open circuits. These lead to distortion of pulse signals transmitted to the controller, triggering timing logic errors.
- Controller Logic Operation Anomaly (Controller) Primarily points to Left Domain Controller Failure. The domain controller is responsible for data fusion and logical judgment from radar sensors. If threshold parameters stored inside it are lost, calculation modules compute incorrectly, or communication buses are disturbed, the controller may falsely mark Ring Time timeout even if the sensor is normal.
### H3 Technical Monitoring & Trigger Logic
The determination of this fault code follows strict electronic electrical architecture logic, with the specific monitoring process as follows:
- Monitoring Target (Monitoring Target): The system continuously collects signal voltage fluctuation characteristics and pulse duration of the rear right center sensor. It focuses on monitoring whether the attenuation curve of the signal after a specific trigger complies with preset physical models.
- Numerical Range & Logic (Numerical Range & Logic): Based on current input data, fault determination does not rely on specific analog voltage thresholds (e.g., $9V$~$16V$), but is based on Time Logic. The system records the signal residual duration in the sensor trigger state; if it exceeds the controller's allowed logic window, it determines an abnormality.
- Specific Operating Condition: This fault is activated and stored only when the vehicle enters an electrical active state. The specific trigger condition is: Ignition switch placed in "ON" position. Once the ignition switch is open and the initialization self-check process is completed, if the above sensor timing parameters are found non-compliant, the system will immediately write the B1B4D00 fault code to record the current state.
diagnostic system records a status marker "Partial Parking Assist System Function Loss", indicating the need to inspect hardware connections or controller logic.
### H3 Core Fault Cause Analysis
Based on technical principles and raw data classification, the core causes of this fault can be investigated by checking the following three key dimensions:
- Hardware Component Failure (Sensor) Primarily Rear Right Center Radar Sensor Failure. As the terminal execution unit for emitting and receiving ultrasonic signals, if the internal oscillation circuit or demodulation module of the sensor is physically damaged, it causes delays in echo signal processing, leading the system to determine that the "Ring Time" does not meet standard characteristics.
- Wiring/Connector Abnormality (Wiring & Connector) Involves Harness or Connector Faults. This includes issues at the physical connection level, such as excessive contact resistance in the power and ground lines from the sensor to the control unit, pin corrosion, short circuits, or open circuits. These lead to distortion of pulse signals transmitted to the controller, triggering timing logic errors.
- Controller Logic Operation Anomaly (Controller) Primarily points to Left Domain Controller Failure. The domain controller is responsible for data fusion and logical judgment from radar sensors. If threshold parameters stored inside it are lost, calculation modules compute incorrectly, or communication buses are disturbed, the controller may falsely mark Ring Time timeout even if the sensor is normal.
### H3 Technical Monitoring & Trigger Logic
The determination of this fault code follows strict electronic electrical architecture logic, with the specific monitoring process as follows:
- Monitoring Target (Monitoring Target): The system continuously collects signal voltage fluctuation characteristics and pulse duration of the rear right center sensor. It focuses on monitoring whether the attenuation curve of the signal after a specific trigger complies with preset physical models.
- Numerical Range & Logic (Numerical Range & Logic): Based on current input data, fault determination does not rely on specific analog voltage thresholds (e.g., $9V$~$16V$), but is based on Time Logic. The system records the signal residual duration in the sensor trigger state; if it exceeds the controller's allowed logic window, it determines an abnormality.
- Specific Operating Condition: This fault is activated and stored only when the vehicle enters an electrical active state. The specific trigger condition is: Ignition switch placed in "ON" position. Once the ignition switch is open and the initialization self-check process is completed, if the above sensor timing parameters are found non-compliant, the system will immediately write the B1B4D00 fault code to record the current state.