P01F1: The lambda sensor (bank 1, sensor 4) has an electrical fault
The lambda sensor (bank 1, sensor 4) has an electrical fault. It may be the part itself, its connector or the wiring.
| Code | P01F1 |
|---|---|
| System | Engine and transmission |
| Group | P01xx, Air and fuel metering |
| Type | Generic: it means the same on every make |
How to read and clear P01F1 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 P01F1 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
- P01EC The engine coolant heater B control has a broken or disconnected wire
- P01ED The engine coolant heater B control gives a lower signal than normal
- P01EE The engine coolant heater B control gives a higher signal than normal
- P01EF The engine coolant heater B control gives readings outside the normal range
- P01F2 The lambda sensor (bank 1, sensor 4) gives a lower signal than normal
- P01F3 The lambda sensor (bank 1, sensor 4) gives a higher signal than normal
- P01F4 The lambda sensor circuit (bank 1, sensor 4) responds slowly
- P01FA The turbocharger output pressure sensor B has an electrical fault
- P0100 Mass or volume air flow sensor circuit fault
- P0101 Air flow sensor range or performance problem
- P0102 Air flow sensor circuit low input
- P0103 Air flow sensor circuit high input
What does code P01F1 mean?
The lambda sensor (bank 1, sensor 4) has an electrical fault. It may be the part itself, its connector or the wiring.
How do you clear P01F1?
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, P01F1 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.
