P2C70Drive Motor A Phase Z 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
- P2C70 means phase Z of drive motor A delivers too little current although the inverter is commanding it. No manufacturer documents P2C70 publicly. GM's missing-phase check for the U/V/W set shows the principle: the 2016 Volt only judges a phase while the rotor angle sits near that phase axis and enough current is requested, and fails it when the peak stays under 9 A, Type A with MIL after one trip. The window matters, because a phase near its zero crossing carries little current even when healthy. For the Z phase of the second set the most likely finds are an open lead or terminal, a burnt connection at the inverter or a sensor stuck at zero. Torque drops and the motor may vibrate. P2C6F is the general Z code, P2C71 the high side, P2C6A and P2C6D the low cases of X and Y.
- What you may notice
- MIL and hybrid or drive warning
- Loss of torque and vibration from the motor under load
- Likely causes
- LikelyPhase Z lead or terminal open or burnt
- PossiblePhase Z current sensor stuck near zero
- PossibleZ leg of the inverter not switching
- RareOpen phase Z winding in the motor
- 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.