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DTC codes / P0Bxx · Hybrid propulsion / P0BFC

P0BFCDrive Motor B Phase W Current Sensor Circuit High

P0BFC indicates that the computer monitoring the drive motor B phase W current sensor has detected an abnormally high signal voltage, which corresponds to a current reading outside the expected range. The sensor circuit is reporting a voltage above the calibrated threshold, suggesting a fault in the sensor, its wiring, or the circuit reference.

SystemPowertrain
Code typeGeneric (all makes)
SeverityHigh
Fix difficultyProfessional
AreaHybrid propulsion

Symptoms you may notice

  • Illumination of the check engine light or service vehicle soon message
  • Often no symptoms besides the warning light
  • Reduced power or limp mode due to hybrid system fault
  • Inconsistent or jerky acceleration from the electric drive motor
  • Possible shutdown of the hybrid system or inability to start
  • Abnormal noise or vibration from the drive motor under load

Common causes, most likely first

  1. Faulty phase W current sensor
  2. Open or shorted signal wire between the sensor and the control module
  3. Poor electrical connection at the sensor or control module connector
  4. High resistance in the sensor ground circuit
  5. Internal fault in the drive motor control module
  6. Electrical interference or damaged shielding on the sensor wiring
  7. Moisture or corrosion in the sensor connector

How to diagnose and fix it

  1. Verify the code with a scan tool and check for any related codes in other modules
  2. Inspect the sensor connector and wiring for damage, corrosion, or loose pins
  3. Measure the sensor reference voltage and ground at the connector
  4. Check the signal wire for continuity and short to voltage or ground
  5. Compare live sensor data with a known-good value or perform a wiggle test
  6. Replace the current sensor if faulty
  7. Repair or replace damaged wiring or connectors as needed

Before replacing the phase W current sensor

  • A high voltage on the current sensor circuit often results from a poor ground connection rather than a failed sensor, so check grounds first.
  • The code can be set by a momentary glitch during harsh acceleration or regenerative braking, so clear it and test-drive to see if it returns.
  • Wiring harness damage from road debris or rodent damage is a common cause that is frequently overlooked.
  • The sensor may be integrated into the drive motor assembly, making replacement more involved than a simple plug-and-play part.
  • A weak 12-volt battery or charging system fault can cause erratic sensor readings and set this code, so verify battery condition.

Can I keep driving with P0BFC?

Driving with this code is not recommended because it can lead to reduced power or sudden loss of hybrid propulsion, increasing the risk of a crash. Have the vehicle inspected by a qualified technician as soon as possible and avoid high-load driving until repaired.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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