Technical Specification for B2FD14B Wireless Charging Over-Temperature Alarm

Detailed Fault Definition

B2FD14B Wireless Charging Over-Temperature Alarm is a key diagnostic trouble code (DTC) within the vehicle electronic control system used to monitor the thermal management status of the wireless charging system. The core role of this DTC lies in ensuring operational safety of the onboard wireless charging module under specific working conditions, supervising and regulating the thermal balance of the charging environment through real-time monitoring by the control unit. This fault code is activated to warn of potential thermal runaway risks when the system detects abnormal temperature rise in the wireless energy transmission area or related hardware components. This definition is built based on the following technical logic:

• System Level: Belongs to the Body Control Module (Body Control Module) or a dedicated wireless charging control unit.
• Functional Logic: Achieves monitoring of thermal effects during non-contact energy transfer, preventing insulation layer damage or component aging caused by overheating.
• Protection Mechanism: Part of an active safety strategy, aiming to avoid safety hazards in high-temperature environments through hardware fusing or software limitations.

Common Fault Symptoms

After the B2FD14B fault code is triggered, the vehicle electronic system provides clear feedback signals to the driver. Based on the "Unable to Charge" description in the original data and extending technical semantics, observable driving experiences and instrument feedback include but are not limited to the following aspects:

• Charging Function Interruption: Wireless charging indicator light turns off or unresponsive, device cannot complete charging process, battery status update stops.
• Thermal Safety Warning: High temperature related hint icons pop up on the vehicle dashboard (such as battery overheating or charging area warning), accompanied by buzzer sound and light alarms.
• Charging Efficiency Zero: Even if the phone is placed in the correct position and system communication is normal, output power is forcibly cut off to $0W$ to maintain safety thresholds.

Core Fault Cause Analysis

Targeting the core information "Mobile Phone Wireless Charging Module Internal Fault" from the original data, combining with automotive diagnostic technology architecture, hardware, wiring and controller logic in this dimension are categorized as follows:

• Hardware Component (Hardware Component)

  • Fault Localization: Mainly points to the mobile phone wireless charging module internals. The module here covers physical components of the device end or receiver end; when internal sensors fail, power conversion chips trigger overheating protection, or thermistors short circuit, it will directly lead to the system judging temperature abnormalities.
  • Component Health Monitoring: Monitoring objects include transmission coils, receiving coils and matching heat dissipation structures; if insulation performance of these components declines causing local hot spots, it will trigger $B2FD14B$ fault code.

• Wiring/Connectors (Wiring and Connectors)

  • Connection Status Evaluation: Involves the transmission path of temperature signals. If there is high impedance contact or open circuit in the sensor signal lines responsible for feeding back temperature data, it may lead to the control unit reading incorrect voltage values, mistakenly judging as over-high temperature.
  • Ground Integrity: If the potential difference between the analog ground (Analog Ground) and digital ground of the wireless charging module exceeds specified range, it may interfere with the accuracy of temperature acquisition signals and cause alarm logic error triggering.

• Controller (Controller Logic)

  • Threshold Judgment Logic: The control unit performs digital processing on the temperature value internally and compares it in real-time with specified threshold. When the algorithm judges the current value meets $T_{current} > T_{threshold}$, the fault code is generated.
  • System Strategy Execution: The controller actively executes power cut-off commands after detecting hardware component anomalies according to preset safety strategies, ensuring electrical safety of the vehicle and electronic equipment.

Technical Monitoring and Trigger Logic

The generation of this fault code does not happen randomly but is based on strict working condition judgment and numerical threshold matching; specific monitoring logic is as follows:

• Monitoring Targets

  • Thermal Sensing Signal: System continuously collects real-time voltage feedback from thermistors (NTC) or infrared sensors in the wireless charging area.
  • Signal Quality Monitoring: Simultaneously monitor stability and duty ratio of temperature sensor signals to prevent false reports caused by instant noise.

• Trigger Numerical Conditions

  • Core Judgment Formula: The baseline for system fault judgment is that the current detected temperature value is greater than the specified threshold.
  • Threshold Range Identification: Original data sets strict specified threshold ($T_{threshold}$); specific values depend on vehicle model configuration and heat dissipation design; once measured temperature $T_{measured} > T_{threshold}$, system will immediately lock fault status.

• Specific Trigger Conditions

  • System Status Requirements: After Vehicle Power-On. Fault monitoring only starts when power system is activated and control unit initialization completed.
  • Dynamic Monitoring Period: Mainly conduct high-frequency dynamic monitoring during wireless charging function activation period or when vehicle is statically parked and wireless charging mode enabled.
  • Fault Code Generation Conditions: After Vehicle Power-On, when system detects temperature greater than specified threshold, control unit will record a fault event, turn on fault indicator light, and generate $B2FD14B$ fault code, ensuring users can immediately know device or module internals exist overheating risks.