P0B25 code meaning
Hybrid/EV Battery A Voltage Low
Powertrain system Generic code P0Bxx codes Check engine light
What P0B25 means
P0B25 sets when the voltage of hybrid/EV battery A drops below the window the controller expects. Bentley uses it in two different systems. In the 48 V Bentley Dynamic Ride anti-roll system it is stored in address 0021 (battery energy control module 2); if the highest and lowest cell readings differ by 0.5 V or more, an internal fault of the super capacitor is assumed and it is replaced. On the Bentayga and Flying Spur Hybrid the code appears in 008C, the high-voltage battery manager, with MIL and red battery warning, and the workshop must involve Bentley product support. GM checks pack undervoltage analogously with P0ABC (below 24 V). Unstable and high readings are P0B24 and P0B26. The driver loses roll control or battery power.
P0B25 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 P0B25
- Bentley Dynamic Ride fault warning, roll control inactive
- MIL on
- Hybrid/EV system or high-voltage battery warning on
- Battery power limited, less electric drive or assist
Common causes of P0B25
- Most likelyInternal fault of the energy store, e.g. Bentley 48 V super capacitor
- PossibleAged or unbalanced cells pulling the unit voltage down
- PossibleDeep discharge after long standstill
- Less likelyVoltage measurement fault in the controller or sense leads
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 P0B25 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. |
| 25 | The exact fault in that area. |
What to do next
- Note P0B25 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 P0B25
What does P0B25 mean?
P0B25 means "Hybrid/EV Battery A Voltage Low". P0B25 sets when the voltage of hybrid/EV battery A drops below the window the controller expects. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B25?
Drive gently and only to a workshop. With P0B25 the car can go into limp mode (reduced power) to protect itself.
Will P0B25 fail an emissions test?
Yes, it can. P0B25 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 P0B25 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P0B25 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.