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.
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 this same explanation and whether it’s confirmed, pending or permanent.
With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.
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 the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.
Similar codes
- P0513 Incorrect immobiliser key
- 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
- P0530 A/C refrigerant pressure sensor: circuit fault
- P0532 A/C refrigerant pressure sensor: low input
- P0533 A/C refrigerant pressure sensor: high input
- 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
P0523 is a generic code, so it means the same on any make, for example on Abarth, Cupra, Jeep, Nissan, Seat, Škoda. See what Final OBD does on your car in makes and models.
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 the faults of every control unit for free, including each make’s own codes, and with Pro explains each one in plain English. Free clears engine faults at no cost.
Coming soon
Mid to late October 2026
If you want to try it in your car before anyone else, send us your email and we will add you as a tester.
info@finalobd.com