What P0520 means
The oil pressure sensor matters for emissions control because modern engines use it as an input – for two-stage or regulated oil pumps, hydraulic cam phasers and GM's cylinder deactivation, whose lifters switch by oil pressure.
How the engine computer detects it
P0520 is the general circuit fault, used differently: Ford gasoline and diesel engines set it for the digital SENT sensor when it reports an internal fault, does not initialize or sends values out of range (lost communication is U0600), after 5 s. GM's 1.4 L turbo with an oil pressure switch sets it when the switch reports pressure although the engine has been off long enough to be pressureless – type C, without warning lamp.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Check engine light (depending on the maker)
- Oil pressure gauge or warning wrong
- Cam phasing or cylinder deactivation possibly disabled
Common causes
- Sensor or switch faulty internally Most likely
- Connector corroded or oily (oil creeping through a leaking sensor) Possible
- Signal line open or shorted to ground Possible
- 5 V reference or supply faulty (usually with other sensor codes) Less likely
How to diagnose P0520
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: oil pressure sensor, sensor wiring, engine control module.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Vehicles that report P0520 most
| Vehicle | Years | Reports | Share | Median miles |
|---|---|---|---|---|
| Jeep Cherokee | 2014 | 6 | 52k | |
| Jeep Grand Cherokee | 2012–2014 | 4 | 68k | |
| Jeep Wrangler | 2013–2014 | 3 | 62k |
Counts of owner complaints to the NHTSA that mention P0520 (19 in total), not failure rates: popular models get more complaints simply because more of them are on the road. Models with fewer than 3 complaints are left out.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 5
- Vehicle speed, idle control and auxiliary inputs
- 20
- Specific fault
Questions drivers ask
Can I drive with code P0520?
Check the oil level before driving. This code can be a faulty sensor or control circuit, but you can't rule out real low oil pressure from the code alone. If the oil pressure warning light comes on, the engine starts ticking or knocking, or the oil is low, don't drive: have it towed.
Will my car pass an emissions inspection with P0520?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
Will P0520 clear by itself?
The light can go off after several drive cycles without the fault, but the code returns if the cause is still there. After a repair, the readiness monitors need a full drive cycle before an inspection.
Can I fix P0520 myself?
Often yes, with an OBD-II scanner and basic tools. Difficulty: easy. Start with the cheapest checks before replacing expensive parts.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.