P2A06

O2 Sensor Negative Voltage Bank 1 Sensor 1

Q: Is it safe to drive with P2A06?

Yes, it won't strip you or cause a no-start. But mixture control is off, so expect worse economy and a likely emissions failure until it's fixed.

Q: Can I just clear P2A06?

It returns within a few drive cycles while the sensor or its wiring is faulty. Fix the cause first.

Fuel & air metering Generic OBD-II Medium

What it means

P2A06 means the upstream (sensor 1) oxygen sensor on bank 1 is producing a negative or out-of-range voltage the controller can't use for mixture control. It's an emissions and fuel-trim fault, not a driveability emergency — the engine still runs and starts. Common causes are a failing O2 sensor, its wiring or connector, or an exhaust leak near the sensor.

Medium

Can I keep driving? Yes — the car will run and drive, but fuel trims and emissions suffer, so fix it before an emissions test or if idle quality drops.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Rough or uneven idle
Higher fuel consumption
Occasional surge or hesitation

Common causes

Most likely first

Faulty upstream (sensor 1) oxygen sensor on bank 1Likely
Short or open in the O2 sensor signal/ground wiringCommon
Corroded or loose O2 sensor connectorCommon
Exhaust leak near the sensor upsetting the readingLess often
Fuel or intake issue skewing the mixtureLess often

How to diagnose & fix

Work through it in order

Read freeze-frame and watch the bank 1 sensor 1 voltage in live data.
Inspect the O2 sensor connector and wiring for corrosion, damage, or a short.
Check for exhaust leaks upstream of the sensor.
Confirm fuel trims and rule out a genuine mixture problem.
Replace the upstream O2 sensor if it reads out of range, then clear and re-test.

FAQ

Quick answers

Is it safe to drive with P2A06?+

Yes, it won't strip you or cause a no-start. But mixture control is off, so expect worse economy and a likely emissions failure until it's fixed.

Can I just clear P2A06?+

It returns within a few drive cycles while the sensor or its wiring is faulty. Fix the cause first.

Read & clear P2A06 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX