P0520high severityPowertrain
Engine Oil Pressure Sensor/Switch Circuit
on 1997 Audi A4 2.8L V6 · AWD
What this code means
Malfunction in the engine oil pressure sensor circuit.
Symptoms
- Check Engine Light
- Oil pressure warning light on
- Gauge reading incorrect
Common causes
- Faulty oil pressure sensor/switch
- Wiring damage
- Low oil level
- Low actual oil pressure
Diagnostic steps
- CHECK OIL LEVEL FIRST
- Test oil pressure with mechanical gauge
- Test sensor resistance
- Inspect wiring
- Check oil pump condition
Repair notes
ALWAYS verify actual oil pressure with mechanical gauge first. Low oil pressure can destroy an engine.
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