P2251 — O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1

What Does P2251 Mean?

P2251 is a diagnostic trouble code indicating: O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P2251

⚠️ Check Engine Light (MIL) illuminated
⚠️ Erratic O2 Sensor Negative Current readings
⚠️ Related system operating intermittently
⚠️ Reduced engine performance

Common Causes

🔍 Wiring issue in O2 Sensor Negative Current circuit (damaged, chafed, or corroded)
🔍 Faulty O2 Sensor Negative Current connector or terminal
🔍 Failed O2 Sensor Negative Current
🔍 ECM/PCM connection issue

Frequently Asked Questions

What does P2251 mean?

P2251 indicates: O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1. The vehicle's computer has detected that the O2 Sensor Negative Current is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P2251?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P2251 for extended periods may cause additional problems.

How much does it cost to fix P2251?

Repair costs for P2251 typically range from $80 to $300, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect and repair O2 Sensor Negative Current wiring and connectors
🔧 Replace faulty O2 Sensor Negative Current

1
Find your vehicle above
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2
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3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P2251: O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1