A faulty motor position sensor (resolver) or its internal wiring.; Damaged, chafed, or corroded wiring in the sensor circuit, especially at connectors or where the harness bends.; A poor electrical connection at the sensor or powertrain control module, such as loose pins or corrosion.; A short to ground or a short to voltage in the sensor signal circuit.; A failed powertrain control module (PCM) or hybrid control module, though this is less common.; Mechanical damage to the motor or resolver assembly from debris, impact, or bearing wear.

DTC codes / P0Axx · Hybrid propulsion / P0A47

P0A47Drive Motor B Position Sensor Circuit Low

Q: What does code P0A47 mean?

Drive Motor B Position Sensor Circuit Low. P0A47 indicates that the powertrain control module has detected an abnormally low voltage signal from the position sensor circuit of drive motor B, which is typically the motor responsible for propulsion in a hybrid or electric vehicle. The computer expects the sensor to report the motor's rotor position within a specific voltage range, and a sustained low reading means the signal is below the acceptable threshold, which can prevent proper motor control.

P0A47 indicates that the powertrain control module has detected an abnormally low voltage signal from the position sensor circuit of drive motor B, which is typically the motor responsible for propulsion in a hybrid or electric vehicle. The computer expects the sensor to report the motor's rotor position within a specific voltage range, and a sustained low reading means the signal is below the acceptable threshold, which can prevent proper motor control.

SystemPowertrain

Code typeGeneric (all makes)

SeverityHigh

Fix difficultyProfessional

AreaHybrid propulsion

Symptoms you may notice

Illumination of the check engine light or hybrid system warning light, often with no other noticeable symptoms.
Reduced power or a limp-home mode that limits vehicle speed and acceleration.
The vehicle may refuse to start or shift into gear because the motor position is unknown.
Rough operation, shuddering, or hesitation during acceleration or regenerative braking.
In some cases, the engine may run continuously or the hybrid system may shut down entirely.

Common causes, most likely first

A faulty motor position sensor (resolver) or its internal wiring.
Damaged, chafed, or corroded wiring in the sensor circuit, especially at connectors or where the harness bends.
A poor electrical connection at the sensor or powertrain control module, such as loose pins or corrosion.
A short to ground or a short to voltage in the sensor signal circuit.
A failed powertrain control module (PCM) or hybrid control module, though this is less common.
Mechanical damage to the motor or resolver assembly from debris, impact, or bearing wear.

How to diagnose and fix it

Perform a visual inspection of the motor position sensor and its wiring harness for obvious damage, corrosion, or loose connectors.
Use a scan tool to check for related codes and freeze-frame data, and verify the sensor voltage reading with a multimeter at the sensor connector.
Check the sensor circuit for continuity, shorts to ground, and shorts to voltage using a wiring diagram and a multimeter.
Inspect the sensor mounting and air gap, and verify that the resolver rotor is not damaged or misaligned.
If the circuit tests good, replace the motor position sensor and clear the codes to see if the fault returns.
If the sensor and wiring are intact, test the powertrain control module inputs and outputs, and replace the module if it is found to be faulty.
After repairs, clear all codes and perform a road test to verify that the code does not reset and that the hybrid system operates normally.

Common Misdiagnosis Traps for P0A47

A low signal from the motor position sensor is often caused by a simple wiring issue rather than a failed sensor, so always inspect the harness and connectors before replacing parts.
The code can be set by a weak or failing 12-volt auxiliary battery, which may cause the control module to misinterpret sensor signals; check battery health first.
On some vehicles, the motor position sensor is integrated into the resolver, and replacing just the sensor may not be possible; the entire resolver assembly may be required.
A faulty inverter or motor control unit can also cause a low signal code, so do not overlook the power electronics when diagnosing.
After replacing the sensor, a relearn or calibration procedure may be necessary for the hybrid control module to recognize the new sensor's position.

Can I keep driving with P0A47?

Driving with P0A47 is not recommended because the vehicle may enter a reduced-power mode or shut down unexpectedly, increasing the risk of a crash. Have the vehicle towed to a qualified repair facility for diagnosis and repair.

Tools that help

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