P0520 on BMW: Causes, Symptoms and Fix Cost
Quick Answer
Not safe to drive
P0520 on a BMW means the ECU sees an out-of-range or implausible signal on the oil pressure sensor circuit. Usually a failed sensor or wiring fault, but it can also flag genuinely low oil pressure, which is why you can't just clear it and drive.
- Severity
- High · Electrical
- Typical repair cost, all makes
- €60-€9000
Connect a standard OBD2 adapter (Bluetooth LE on iPhone) to your BMW and Skanyx tells you what P0520 means on that engine, whether it is safe to keep driving, and what the fix should cost. Free on iPhone and Android.
Get Skanyx freeWhat does P0520 mean on a BMW?
The Quick Answer above is the generic definition. What follows is the model-specific detail for the BMW models that log P0520.
BMW 3-Series
2012-2019
The N20 has a separate engine oil pressure and temperature sensor on the side of the engine block, reached after removing the throttle body; the oil level sensor in the sump is a different part and does not report pressure. There is no dipstick, so check the level electronically and verify actual pressure with a mechanical gauge before spending money.
Source: bmwx3tech.com
Sources
- bmwx3tech.com bmwx3tech.com/1002/removing_and_installing_replacing_engine_oil_pressure_tempera
What causes P0520 on a BMW?
Beyond the generic causes listed on the main P0520 page, these are the patterns noted for BMW models:
Oil pressure/temperature sensor internal failure
: BMW 3-Series
Oil or corrosion in the sensor connector
: BMW 3-Series
Genuinely low oil pressure, to be confirmed with a mechanical gauge
: BMW 3-Series
How to diagnose P0520 on a BMW with OBD2
- Check oil level on the dipstick (or via the electronic gauge on BMW/Audi) before anything else. If it's low, top up and inspect for leaks.
- Connect a mechanical oil pressure gauge at the sensor port. Compare idle and 2500 rpm readings to the service manual spec (typically 25-30 psi (1.7-2.1 bar) hot idle, 55-65 psi (3.8-4.5 bar) at 2500 rpm on most engines).
- If real pressure is in spec, unplug the sensor connector and inspect for oil intrusion, green corrosion, or spread pins.
- Key on, engine off: back-probe the connector. Confirm 5V reference (variable sensors) or battery voltage (switches), a clean ground, and continuity on the signal wire back to the PCM.
- Substitute a known-good sensor, clear the code, and retest under the conditions that set it.
- If the code returns with a good sensor and clean wiring, scope the signal for dropouts during a road test.
- If actual pressure is low, drop the pan and inspect the pickup screen for sludge before condemning the pump.
How much does P0520 cost to fix on a BMW? (EUR)
Estimated repair costs for P0520 in EUR, compiled across makes. Expect BMW parts and labour towards the upper end of each range.
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| Replace oil pressure sensor/switch | €20–€90 | €40–€150 | €60–€240 | Moderate |
| Repair damaged connector or pigtail | €10–€60 | €60–€180 | €70–€240 | Moderate |
| Oil and filter change with correct viscosity | €40–€100 | €30–€70 | €70–€170 | Easy |
| Replace oil pump and pickup | €150–€450 | €400–€1200 | €550–€1650 | Professional |
| Engine overhaul or replacement for worn bearings | €1500–€6000 | €1000–€3000 | €2500–€9000 | Professional |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
Codes related to P0520
These codes are often seen alongside P0520 or point to related issues, on any make:
- P0521 · BMW
- P0522
- P0523
- P0524
Looking for the full P0520 reference (all makes, full diagnosis flow, complete repair cost matrix)? See the main P0520 guide