P0A6ADrive Motor B Phase V Current Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0A6A is GM's open-circuit test for phase V of drive motor B. The controller checks each phase on its own as the rotor turns; for phase V it looks at the window of 30 degrees either side of the V axis, where the current should be largest. With the inverter above 50 V in normal PWM and a squared current command above 900 A² (2016 Volt) or 4,900 A² (2018 and 2019 tables), a peak below 9 A for 0.4 s out of 0.6 s is a Type A failure with MIL after one trip. The 2016 Volt table describes this motor B code with the words drive motor A, an evident copy slip. A missing V current points to a broken lead, a dead switch or a sensor stuck at zero. P0A6B is the high side, P0A67 and P0A6D phases U and W, P0A61 the motor A code.
- What you may notice
- MIL and propulsion system warning after the first trip
- Vibration or uneven torque from motor B before shutdown
- Likely causes
- LikelyPhase V lead, connector or bolted terminal of motor B open
- PossiblePhase V switch of the motor B inverter not switching
- PossiblePhase V current sensor output stuck at zero
- RareOpen phase V winding in motor B
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €300 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.