P0A1F: Battery energy control module fault
The unit that monitors the high-voltage battery has detected an internal or power supply fault. The 12 V battery, a fuse or a connector is typical.
| Code | P0A1F |
|---|---|
| System | Engine and transmission |
| Group | P0Axx, Hybrid and electric |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P0A1F means
The battery energy control module measures the high-voltage battery’s voltage, current and temperature and reports its condition to the rest of the hybrid system. This code means that module has a fault of its own, for example in its power supply, memory or measuring circuits. Without its data, the car limits or blocks use of the battery.
Most common causes
- Low 12 V battery or loose terminals
- Blown power fuse for the module
- Loose or corroded module connector
- Moisture or spilled liquid near the high-voltage battery, where the module usually sits
- Faulty battery control module or one needing a software update
Symptoms
- Engine warning light and hybrid system warning
- Car will not go into READY mode or start
- Limited power or no electric mode
- Battery charge gauge showing nothing
Can you drive with P0A1F?
With care If the car starts you can drive with care, but it may lose hybrid mode or fail to restart. Get it to a hybrid specialist soon.
Open the bonnetthe in-depth explanation
How to check it
Check the 12 V battery first: below about 12.2 V at rest, charge it and read the codes again. Also check for spills around the rear seats or boot, where the hybrid battery usually sits.
How to read and clear P0A1F with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0A1F with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P0A1B The traction motor control unit A is not working properly
- P0A1C The traction motor control unit B is not working properly
- P0A1D There is a fault in the control unit for the hybrid powertrain
- P0A1E There is a fault in the starter and generator control unit
- P0A20 The engine torque sensor gives a higher signal than normal
- P0A21 The engine torque sensor fails now and then
- P0A22 The generator torque sensor has an electrical fault
- P0A23 The generator torque sensor gives readings outside the normal range
- P0A0F Engine failed to start
- P0A7F Hybrid battery pack deterioration
- P0A80 Replace hybrid battery pack
- P0A94 DC/DC converter performance
What does code P0A1F mean?
The battery energy control module measures the high-voltage battery’s voltage, current and temperature and reports its condition to the rest of the hybrid system. This code means that module has a fault of its own, for example in its power supply, memory or measuring circuits. Without its data, the car limits or blocks use of the battery.
Can you drive with P0A1F?
If the car starts you can drive with care, but it may lose hybrid mode or fail to restart. Get it to a hybrid specialist soon.
How do you clear P0A1F?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0A1F comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
