P0AC2 code meaning
Hybrid/EV Battery Pack Current Sensor A Circuit High
Powertrain system Generic code P0Axx codes Check engine light
What P0AC2 means
With P0AC2 the current sensor output sits above its valid window, which after conversion would mean an implausibly large current in the opposite direction to P0AC1. GM's 2016 and 2019 hybrid tables set it when the Hall-effect sensor reads above 274.6 A in 8 of 10 samples taken every 25 ms, again as Type A with immediate MIL. The 2013 table for an earlier pack uses an output above 4.65 V, roughly 215 A, with 7 of 10 samples and Type B. A signal shorted to the 5 V supply or an open sensor ground are common reasons. Because the controller can no longer count charge, it caps battery power; the low limit is P0AC1 and implausible offsets are P0AC0.
P0AC2 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0AC2
- Hybrid system or check engine warning on
- Battery power limited, engine runs more often
Common causes of P0AC2
- Most likelySensor ground open
- PossibleSignal wire shorted to the 5 V supply or another voltage
- PossibleHall current sensor failed internally
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery pack current sensor aWiring harnessBms
What each part of P0AC2 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| C2 | The exact fault in that area. |
What to do next
- Note P0AC2 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0AC2
What does P0AC2 mean?
P0AC2 means "Hybrid/EV Battery Pack Current Sensor A Circuit High". With P0AC2 the current sensor output sits above its valid window, which after conversion would mean an implausibly large current in the opposite direction to P0AC1. It is a generic code, so it means the same on every make.
Is it safe to drive with P0AC2?
Drive gently and only to a workshop. With P0AC2 the car can go into limp mode (reduced power) to protect itself.
Will P0AC2 fail an emissions test?
Yes, it can. P0AC2 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0AC2 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0AC2 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.