The rotor position of a traction motor is read by a resolver: one excitation coil and two pickup coils that return sine and cosine signals. P0A3F is the basic circuit code for motor A and mostly means the signal is gone. GM sets it when the sine or cosine amplitude drops below 2.3 V (Type A, one trip in the 2011 and 2016 tables); Mitsubishi (2023 Outlander PHEV front motor) watches the excitation voltage and fails it outside 1.0 to 2.86 V for 0.14 s. Field causes: a spread terminal at the X2 connector of the Chevrolet Bolt, low 12 V supply on the 2014 Subaru XV Crosstrek Hybrid (software fix), Stellantis Pacifica Hybrid. P0A40 covers a degraded signal. Expect lost propulsion or no electric drive.
High severity. Can I keep driving?If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.
Symptoms
- Sudden loss of propulsion, sometimes normal again after a restart
- MIL and hybrid/EV system warning on
- Vehicle will not enter ready mode or electric drive is disabled
Most likely causes
- Spread or poorly seated terminal at the resolver connector (documented on the Chevrolet Bolt)
- Open or shorted excitation, sine or cosine wire between motor and inverter
- Low 12 V auxiliary battery voltage disturbing the motor control module (Subaru, fixed by reprogramming)
- Resolver coil failed inside the motor
- Faulty resolver excitation or input stage in the inverter/motor control module
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- It can trigger limp mode.
- It affects emissions.
What each character of P0A3F means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- A: Hybrid or air and fuel
- 3F: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0A3F?
If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.
What causes code P0A3F?
The most common causes are: spread or poorly seated terminal at the resolver connector (documented on the Chevrolet Bolt); open or shorted excitation, sine or cosine wire between motor and inverter; low 12 V auxiliary battery voltage disturbing the motor control module (Subaru, fixed by reprogramming).
Related codes
- P0A40Drive Motor A Position Sensor Circuit Range/Performance
- P0A41Drive Motor A Position Sensor Circuit Low
- P0A42Drive Motor A Position Sensor Circuit High
- P0A43Drive Motor A Position Sensor Circuit Intermittent
- P0A44Drive Motor A Position Sensor Circuit Overspeed
- P0A45Drive Motor B Position Sensor Circuit
- P0C52Drive Motor A Position Sensor Circuit A Low
- P0C53Drive Motor A Position Sensor Circuit A High
Sources
- gsi.ext.gm.com: 11OBDG01 HYBRID Diagnostics
- gsi.ext.gm.com: 16OBDG02 Hybrid Diagnostics
- mitsubishitechinfo.com: N503240210000800USA
- static.nhtsa.gov: MC 10232147 0001
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.