OBD-II diagnostic trouble code
P0131Caution

O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)

The front bank-1 oxygen sensor's voltage is staying persistently low, often because the sensor has aged out or the engine is genuinely running lean.

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Code names are compiled from open/standardized SAE and ISO references. Explanations, symptoms, causes and fixes are original. Covers generic (P0/C0/B0/U0) codes only — manufacturer-specific codes are planned for a future update.

Frequently asked questions

Can I drive with P0131?

You can usually keep driving with P0131, but don't put it off — the underlying cause can get worse or lead to further damage the longer it goes unaddressed. Get it diagnosed as soon as you reasonably can.

How much does it cost to fix P0131?

The cost varies too much by cause and vehicle to give a single figure here — a diagnosis will narrow it down.

What causes P0131?

AS
Reviewed by Artyom SemenovAutomotive Editor · Fact-checked by Yauheni Kapliarchuk, Editor-in-Chief
Code names compiled from open SAE/ISO references; explanations and repair guidance are original editorial content
Last verified: 09 Jul 2026 · Our methodology