P0131Medium severity

O2 Sensor Low Voltage B1S1

The front oxygen sensor on bank 1 is reading a consistently low voltage.

Safe to Drive?
Yes

Informational only. Consult a qualified mechanic.

Estimated Repair Cost
$100 - $350
Common Causes
  • Vacuum leak
  • Faulty O2 sensor
  • Exhaust leak
  • Fuel pressure issue
Recommended Action

Check for vacuum and exhaust leaks, then replace O2 sensor.

What does P0131 mean?

The P0131 OBD-II diagnostic trouble code (DTC) indicates: o2 sensor low voltage b1s1. This is a medium-severity powertrain code that your vehicle's onboard diagnostics system triggers when the front oxygen sensor on bank 1 is reading a consistently low voltage. If your check engine light is on with this code, the vehicle is generally safe to drive, but you should have it inspected soon.

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