P2804: The gearbox B position sensor fails now and then
The gearbox B position sensor fails now and then. It is usually the part, its wiring or a connector with poor contact.
| Code | P2804 |
|---|---|
| System | Engine and transmission |
| Group | P28xx, Transmission and engine |
| Type | Generic: it means the same on every make |
How to read and clear P2804 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 P2804 with its description and whether it’s confirmed, pending or permanent.
This code is usually stored by the gearbox control unit. If the car reports it over standard OBD, you read it for nothing with FREE; to read it straight from the gearbox control unit, with its description and clearing, you need PRO.
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
- P2800 There is a fault in the input from sensor B for gearbox park, reverse, neutral
- P2801 The gearbox B position sensor gives readings outside the normal range
- P2802 The gearbox B position sensor gives a lower signal than normal
- P2803 The gearbox B position sensor gives a higher signal than normal
- P2805 Gearbox position sensors A and B do not agree
- P2806 The gearbox position sensor is misaligned
- P2807 The pressure control solenoid G is not working properly
- P2808 The pressure control solenoid G has got stuck
What does code P2804 mean?
The gearbox B position sensor fails now and then. It is usually the part, its wiring or a connector with poor contact.
How do you clear P2804?
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, P2804 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.
