P040B: The exhaust gas recirculation temperature sensor A gives readings outside the
The exhaust gas recirculation temperature sensor A gives readings outside the normal range. It is usually the sensor itself, its wiring or a real fault in what it measures.
| Code | P040B |
|---|---|
| System | Engine and transmission |
| Group | P04xx, Emissions control |
| Type | Generic: it means the same on every make |
How to read and clear P040B 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 P040B 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
- P0407 EGR sensor B circuit low
- P0408 EGR sensor B circuit high
- P0409 EGR sensor A circuit malfunction
- P040A The exhaust gas recirculation temperature sensor A has an electrical fault
- P040C The exhaust gas recirculation temperature sensor A gives a lower signal than
- P040D The exhaust gas recirculation temperature sensor A gives a higher signal than
- P040E The exhaust gas recirculation temperature sensor A fails now and then
- P040F EGR temperature sensors A and B do not agree
- P0400 Exhaust gas recirculation (EGR) flow malfunction
- P0401 Exhaust gas recirculation (EGR) flow insufficient
- P0402 Exhaust gas recirculation (EGR) flow excessive
- P0403 EGR control circuit malfunction
What does code P040B mean?
The exhaust gas recirculation temperature sensor A gives readings outside the normal range. It is usually the sensor itself, its wiring or a real fault in what it measures.
How do you clear P040B?
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, P040B 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.
