O2 Sensor Low Voltage B1S1
The front oxygen sensor on bank 1 is reading a consistently low voltage.
Informational only. Consult a qualified mechanic.
- Vacuum leak
- Faulty O2 sensor
- Exhaust leak
- Fuel pressure issue
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.
Use Your Service Book to log this diagnostic trouble code to your vehicle's service history, track repairs, and get maintenance reminders — all for free.
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