Engine Oil Pressure Sensor Circuit Low Voltage
This code points to a low voltage reading from the engine oil pressure sensor.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine oil pressure sensor is sending a reading that is too low, indicating there might not be enough oil pressure circulating in the engine.
What the computer is actually seeing
The engine control module (ECM) expects a voltage range from the oil pressure sensor between 0.5V to 4.5V, indicating the oil pressure status. When it sees a voltage below 0.5V, it triggers this fault code.
What a healthy reading looks like
Expected oil pressure from the sensor should be between 10-40 PSI at idle and up to 70 PSI during acceleration depending on engine specifications.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check oil level; should be at the correct mark on the dipstick. If low, top off with the right type of oil.
- 2Inspect the wiring harness and connectors at the oil pressure sensor for damage or corrosion. Repair as necessary.
- 3Test the oil pressure sensor: unplug it and measure the resistance/voltage. It should give a reading according to expected values above.
- 4If the sensor checks out, use a mechanical oil pressure gauge to verify actual oil pressure at the engine. Replace the oil pump if pressure is low despite a good sensor.
- 5If all checks out but the code persists, consider replacing the oil pressure sensor.
Common causes
- Faulty oil pressure sensor
- Wiring issues (shorts or breaks)
- Low engine oil level
- Oil pump failure
- Oil viscosity too thick for temperatures
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, driving with low oil pressure can cause severe engine damage.
Will this code come back after clearing?
It may come back if the underlying issue isn't resolved, especially if the oil pressure is genuinely low.
Why does this code pair with SPN 801?
SPN 801 is a general oil pressure fault that often accompanies conditions causing SPN 802.
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