Engine Oil Pressure Sensor Circuit Malfunction
The P0520 code indicates a malfunction in the engine oil pressure sensor or its circuit. The Powertrain Control Module (PCM) detects an electrical issue, such as an open or short circuit, in the sensor's wiring or the sensor itself. This sensor monitors oil pressure to ensure proper engine lubrication; a fault can lead to inaccurate readings or a warning light.
01. Most Common Causes
- Faulty engine oil pressure sensor
- Open or short in the sensor wiring or connector
- Low engine oil level or pressure
- Damaged PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Oil pressure warning light on
- Engine noise or knocking due to low oil pressure
- Erratic oil pressure gauge reading
03. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P0520 is present.
Step 2: Check engine oil level and condition; top off or change if needed.
Step 3: Inspect the oil pressure sensor wiring and connector for damage, corrosion, or loose connections.
Step 4: Test the sensor's resistance and voltage with a multimeter; compare to specs.
Step 5: If wiring and sensor are okay, test oil pressure mechanically using a gauge to rule out actual low pressure.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Low oil pressure can cause severe engine damage. Have it diagnosed immediately.
How much does it cost to fix?▼
Typically $50-$150 for sensor replacement; more if wiring repair or oil pressure issues are found.