Czujnik IBS akumulatora — sygnał nieprawidłowy (BMW)
P0B25
WysokiHybrid Battery 'A' Voltage Too Low. The powertrain control module has detected that the voltage in the traction battery module has dropped below the permissible threshold.
OBD-II (EN): Hybrid Battery Voltage 'A' Low
Code P0B25 means the powertrain control module has detected too low voltage in hybrid battery 'A'. The cause may be cell wear, a BMS module fault, or a high-voltage wiring problem. Due to the nature of the high-voltage system, diagnosis by a certified hybrid vehicle service center is recommended.
Symptoms
- Warning on the dashboard (hybrid system light or MIL) - Power limitation or fail-safe mode (limp mode) - Reduced availability of regenerative braking energy - Reduced driving economy (higher fuel consumption or reduced electric range) - Possible automatic shutdown of the electric motor - Hybrid battery not charging or charging incorrectly
Possible causes
- Damaged or worn traction battery cells (capacity degradation) - Faulty Battery Management System (BMS) - Open circuit or short circuit in the battery 'A' circuit wiring/connectors - Damaged relay or fuse in the high-voltage circuit - Malfunction of the battery cooling system (overheating causing voltage drop) - Long vehicle standstill causing deep battery discharge
Affected systems
Related codes
Pogorszenie sprawności baterii HV — niska SOH
Niskie napięcie w obwodzie czujnika napięcia pakietu baterii hybrydowej "D". Moduł sterowania baterią wykrył zbyt niskie napięcie w gałęzi pomiarowej "D" pakietu trakcyjnego.
Wymiana baterii hybrydowej — wymagana
Suggested Hybspec services
Based on the systems affected by this code, we will most likely start with:
Sources and further reading
Does code P0B25 require professional diagnostics?
The code alone is not enough. To find the cause, you need to read live data, check freeze frame conditions, and compare with vehicle behavior. Book a diagnostic session.
