P0EF7 code meaning
Battery Charger A Input Voltage Sensor B Circuit
What P0EF7 means
P0EF7 stands for an electrical fault in the second input voltage sensor of on-board charger A, the measuring channel that reads the AC supply voltage coming from a wallbox, station or household outlet. Chargers designed for several phases or split-phase supply may carry more than one such channel; the first one, sensor A, uses P0D3D to P0D41. This general code applies when the signal is unusable but not classified as range, low or high, which are P0EF8, P0EF9 and P0EFA. No manufacturer documents P0EF7 publicly. In its 2019 plug-in hybrid tables GM reads sensor A through a pulse duty ratio, so a broken line shows up as a stuck 0 % or 100 %. CARB requires plug-in vehicles to monitor charging system performance. As long as the supply voltage cannot be confirmed, AC charging is refused or limited.
P0EF7 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0EF7
- AC charging does not start or stops shortly after start
- Charging fault message in the cluster or app
- DC fast charging usually unaffected
Common causes of P0EF7
- Most likelyFault in the voltage sensing stage inside the charger
- PossibleOpen or high-resistance signal line between sensor and controller
- Less likelyCorroded low-voltage connector at the charger
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Battery charger a input voltage sensor bWiring harnessOn board charger
What each part of P0EF7 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| F7 | The exact fault in that area. |
What to do next
- Note P0EF7 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 P0EF7
What does P0EF7 mean?
P0EF7 means "Battery Charger A Input Voltage Sensor B Circuit". P0EF7 stands for an electrical fault in the second input voltage sensor of on-board charger A, the measuring channel that reads the AC supply voltage coming from a wallbox, station or household outlet. It is a generic code, so it means the same on every make.
Is it safe to drive with P0EF7?
P0EF7 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P0EF7 fail an emissions test?
P0EF7 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P0EF7 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P0EF7 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.