# Heated oxygen sensor (HO2S) 2, bank 1 - circuit negative voltage

Source: https://obdlens.com/codes/p2a07/
Last built: f308d1b1847024568b3a

[Diagnostic knowledge](https://obdlens.com/knowledge/) / P2A07 — Heated oxygen sensor (HO2S) 2, bank 1 - circuit negative voltage

P2A07

P2A07 is described as “Heated oxygen sensor (HO2S) 2, bank 1 - circuit negative voltage” in the Generic OBD2 reference. 

Some scan tools (for example GM and Ford dealer tools) display this code with a failure-type suffix, such as P2A07-00 or P2A07:00; the base code P2A07 is the same.

## What do Bank and Sensor mean?

Bank 1 is the side containing cylinder 1. Bank 2 is the other side on V or flat engines; inline engines have only Bank 1. Cylinder numbering depends on the engine, so check the manufacturer’s layout.

For exhaust oxygen sensors, Sensor 1 is upstream, closest to the engine; Sensor 2 is downstream, after the catalyst. Confirm the exact sensor layout in the vehicle’s service information.

Other-bank reference: [P2A10](https://obdlens.com/codes/p2a10/). A paired definition does not prove that your engine has both banks.

Generic OBD2

## Generic OBD2: P2A07

enHeated oxygen sensor (HO2S) 2, bank 1 - circuit negative voltage

Reference namespace: obd2

Source revision: legacy-2.2.20

Generic OBD2 definition; confirm the protocol and vehicle-specific service information.

## What should I check before using this definition?

Keep the full code, module, status and freeze-frame data. Confirm the vehicle’s make, model, year and current manufacturer service information before choosing a repair. This entry does not identify a failed part by itself.

[Organize a scan report or recording](https://obdlens.com/analyze/)

Source and applicabilityOBD Lens production library legacy-owner-2026-11-02-v84-evidence. This is a scoped technical reference, not a scan of your car. A catalog relationship does not certify that every ECU, year or engine returns the same signal or code definition.

[Read the reference method](https://obdlens.com/about/)

## What does P2A07 mean?

Heated oxygen sensor (HO2S) 2, bank 1 - circuit negative voltage. 1 reference families define this identifier: Generic OBD2.

## Is P2A07 a generic or manufacturer-specific code?

This code has a generic OBD-II prefix. Confirm the reference scope shown above.

## Can P2A07 tell me which part has failed?

This entry does not identify a failed part by itself. Confirm the vehicle’s make, model, year and current manufacturer service information before choosing a repair.

## Continue with your vehicle

Use a specific profile to explore its enhanced signals and assigned code-reference families.

[Find a vehicle profile](https://obdlens.com/vehicles/)

## Read data from your car

Basic diagnostics and supported enhanced PID access remain free.

[Explore OBD Lens App](https://obdlens.com/app/)

OBD Lens reference library · catalog legacy-owner-2026-11-02-v84-evidence. [Sources and scope](https://obdlens.com/about/)

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Reference-family membership is not proof that a code applies to every listed ECU or vehicle. Runtime-ready definitions are not physical-vehicle validation. Unavailable readings must not be treated as zero. App and hardware sale availability must be checked separately.