P0523: Oil pressure sensor/switch high voltage
The ECU sees too high a voltage from the oil pressure sensor. Usually a broken wire, a loose connector or the sensor itself.
| Code | P0523 |
|---|---|
| System | Engine and transmission |
| Group | P05xx, Speed, idle and auxiliary inputs |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P0523 means
The oil pressure sensor sends a voltage that rises with pressure. High voltage means the ECU sees a value above what should be possible, normally because the circuit is open or a wire is touching a live feed. Only rarely is the pressure genuinely too high.
Most common causes
- Sensor connector unplugged or with loose pins
- Broken sensor signal or earth wire
- Bare wire touching a positive feed
- Faulty oil pressure sensor
- Oil far too thick or a stuck pump relief valve, which is uncommon
Symptoms
- Oil pressure gauge at maximum, if fitted
- Oil pressure light not warning when it should
- Engine warning light on
Can you drive with P0523?
With care It is nearly always electrical, but until it is fixed the car will not warn you if pressure drops. Keep an eye on the oil level and get it repaired soon.
Open the bonnetthe in-depth explanation
How to check it
Check the oil level and the sensor connector. On the scanner, if pressure reads high even with the engine off and the ignition on, the fault is electrical or in the sensor, not in the engine.
How to read and clear P0523 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 P0523 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
- P051F The positive sump ventilation filter restriction is not working properly
- P0520 Oil pressure sensor/switch circuit malfunction
- P0521 Oil pressure sensor/switch range/performance
- P0522 Oil pressure sensor/switch low voltage
- P0524 Engine oil pressure too low
- P0525 The cruise control servo control gives readings outside the normal range
- P0526 The fan speed sensor has an electrical fault
- P0527 The fan speed sensor gives readings outside the normal range
- P0500 Vehicle speed sensor malfunction
- P0501 Vehicle speed sensor range/performance
- P0502 Vehicle speed sensor circuit low input
- P0503 Vehicle speed sensor intermittent, erratic or high
What does code P0523 mean?
The oil pressure sensor sends a voltage that rises with pressure. High voltage means the ECU sees a value above what should be possible, normally because the circuit is open or a wire is touching a live feed. Only rarely is the pressure genuinely too high.
Can you drive with P0523?
It is nearly always electrical, but until it is fixed the car will not warn you if pressure drops. Keep an eye on the oil level and get it repaired soon.
How do you clear P0523?
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, P0523 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.
