P2B6F23 - P2B6F23 Electronic Fan 1 Overload

P2B6F23 Electronic Fan 1 Overload

Fault Condition Definition

DTC P2B6F23 in the vehicle thermal management system is defined as "Electronic Fan 1 Overload". This diagnostic identifier indicates that the Integrated Vehicle Controller (IVC) or Powertrain Control Module has detected that the electronic fan motor unit exceeds the preset load threshold during operation. From a system architecture perspective, this fault code reflects that the active cooling components of the cooling system cannot maintain expected current output characteristics, resulting in abnormal electrical load increases. The control unit identifies states of excessive physical mechanical resistance or drive logic failure by monitoring current characteristics of the drive circuit and feedback loop signals in real-time, determining an overload event to prevent damage to the electronic motor and ensure safe operation of the thermal management subsystem.

Common Fault Symptoms

When the system records DTC P2B6F23, the vehicle may present the following driving experiences or instrument panel feedback during actual operation:

• Engine Bay Temperature Abnormality: Due to improper functioning of the cooling fan, coolant circulation efficiency decreases, potentially causing the dashboard engine water temperature warning light to illuminate.
• Abnormal Fan Operation Sound: The driver may hear abnormal noise from the front of the car when the engine is running, manifesting as sticking sound during fan stall or vibration noise due to mismatched speed.
• Reduced Thermal Management Efficiency: Under high load conditions such as climbing or highway driving, insufficient cooling capacity may cause an increase in cooling system pressure.
• Change in Diagnostic Readiness Status: The Malfunction Indicator Lamp (MIL) on the vehicle dashboard may light up, indicating that the control unit has activated DTC settings and entered a fault lock status.

Core Fault Cause Analysis

According to raw data analysis, the causes of DTC P2B6F23 can be summarized into the following three technical dimensions:

• Hardware Component Failure: Electronic Fan Stall Fault. Refers to physical structure jamming, bearing wear, or internal coil short circuit of the drive motor, causing the motor rotor unable to rotate freely or excessive resistance before reaching rated speed, triggering overload protection.
• Controller Logic Abnormality: Integrated Vehicle Controller Failure. Refers to drift in power drive modules (IGBT or MOSFET) or current sampling circuits inside the control unit, causing the controller to incorrectly issue continuous high-current commands to the motor group, even if the motor is not stalled, belonging to hardware or software faults at the logic operation level.
• Wiring and Connector Connection: Although raw data does not explicitly state this, such overloads are often accompanied by physical wiring connection issues. For example, poor motor ground or excessive resistance in power cables will cause abnormal voltage sampling at the controller end, misjudging load as too heavy and triggering the fault code.

Technical Monitoring and Trigger Logic

The determination of this fault code is based on the real-time monitoring strategy of the integrated vehicle diagnostic system, its trigger logic strictly depends on the following conditions and configuration requirements:

• Trigger Enable State: Only when DTC Setup Enabled (Diagnostic Trouble Code Setup Enabled) is active will the system continuously compare fan load against thresholds. Relevant data will be ignored if the vehicle is not in a diagnostic monitoring activated state.
• Power Voltage State: The effective monitoring window for fault determination is IGN ON (Ignition Switch On). In this condition, the integrated vehicle controller receives working voltage and initiates dynamic load scanning of the electronic fan drive circuit.
• Dynamic Monitoring Thresholds: During the period when IGN is ON and the fan is activated, the system calculates motor input current vs expected power model in real-time. Once actual measured load exceeds allowed safe upper limit, fault setting conditions are met (Setting Conditions). This logic ensures faults are only correctly identified and recorded when the vehicle is powered on and needs cooling.