OBD-II Generic Error Code P2247: How to Fix It

Q: Can I drive my car with a P2247 code?

You can typically drive short distances with P2247 active, but it is not recommended for extended driving. The faulty O2 sensor reference signal means the PCM cannot accurately control the air-fuel mixture on Bank 2, which can lead to increased fuel consumption, rough running, and over time may cause damage to the catalytic converter on that bank. Address the code as soon as reasonably possible.

Q: What is Bank 2 Sensor 1 on my vehicle?

Bank 2 refers to the side of the engine that does NOT contain cylinder #1. On most V6 and V8 engines, Bank 2 is on the passenger side, though this varies by manufacturer and engine orientation. Sensor 1 always refers to the upstream oxygen sensor — the one located before (upstream of) the catalytic converter. If you are unsure, consult your vehicle's service manual or a reliable vehicle-specific forum for your exact make and model.

Q: Will replacing the oxygen sensor always fix P2247?

Not always. P2247 is specifically a reference voltage circuit fault, which means the problem could be in the wiring harness, the connector, the oxygen sensor itself, or the PCM. Simply replacing the sensor without testing the reference voltage at the connector may result in the code returning if a wiring or PCM issue is the real cause. Always diagnose the circuit before replacing parts.

Q: How much does it cost to fix a P2247 code?

Costs vary widely depending on the root cause. An oxygen sensor replacement typically costs $50–$200 for the part, plus $50–$150 in labor at a shop. Wiring repairs can range from $75–$300 depending on the extent of damage. If a PCM reflash is needed, expect $100–$200 at a dealership. PCM replacement is significantly more expensive, often $500–$1,500 or more including programming. Diagnosing and fixing wiring yourself with the right tools can save substantial labor costs.

Q: Can a bad ground cause the P2247 code?

Yes, absolutely. A poor or corroded engine ground, or a bad ground specific to the O2 sensor circuit, can cause incorrect reference voltage readings that trigger P2247. When diagnosing this code, always check that the O2 sensor's ground wire has a clean, solid ground connection with near 0 ohms resistance to battery negative. Cleaning corroded ground connection points is a simple, free fix that is often overlooked.

Abstract

The P2247 error code indicates a problem with the Heated Oxygen Sensor (HO2S) reference voltage circuit on Bank 2, Sensor 1 — the upstream oxygen sensor on the engine bank that does NOT contain cylinder #1. This code typically means the PCM (Powertrain Control Module) is detecting an incorrect or missing reference voltage signal from that sensor, which can affect fuel trim and emissions. Left unaddressed, it can cause poor fuel economy, failed emissions tests, and potential catalytic converter damage over time.