P0B23 code meaning
Hybrid/EV Battery A Voltage
Powertrain system Generic code P0Bxx codes Check engine light
What P0B23 means
P0B23 is the general fault for the voltage of hybrid/EV battery A, the first of up to four sub-batteries or energy stores (A to D) that the battery controller evaluates separately; which physical unit carries the letter is up to the manufacturer. The code says that the measured voltage of this unit no longer fits the expected value, without the finer split into unstable (P0B24), low (P0B25) or high (P0B26). No manufacturer documents P0B23 publicly; Bentley and Stellantis bulletins only show the specific siblings. GM watches the comparable whole-pack voltage with P0ABB to P0ABD. CARB requires the voltage sensors and cells of the hybrid storage to be monitored, with fault codes that point to the smallest replaceable unit.
P0B23 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B23
- Hybrid/EV system or high-voltage battery warning on
- MIL on
- Battery power limited, less electric drive or assist
- Charging or recuperation restricted
Common causes of P0B23
- PossibleWeak or failing cells or module in battery A
- PossibleFault in the voltage sense leads or connectors of battery A
- Less likelyBattery controller software or internal measurement fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery aBms
What each part of P0B23 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| 23 | The exact fault in that area. |
What to do next
- Note P0B23 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 P0B23
What does P0B23 mean?
P0B23 means "Hybrid/EV Battery A Voltage". P0B23 is the general fault for the voltage of hybrid/EV battery A, the first of up to four sub-batteries or energy stores (A to D) that the battery controller evaluates separately; which physical unit carries the letter is up to the manufacturer. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B23?
Drive gently and only to a workshop. With P0B23 the car can go into limp mode (reduced power) to protect itself.
Will P0B23 fail an emissions test?
Yes, it can. P0B23 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 P0B23 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P0B23 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.