OBD-II Generic Error Code P2248: How to Fix It

Q: What does P2248 mean on my vehicle?

P2248 means your vehicle's PCM (computer) has detected that the reference voltage signal from the upstream heated oxygen sensor on Bank 2 (the engine bank that does not contain cylinder #1) is not performing within the expected range. This reference voltage is typically 5 volts and is used by the sensor to accurately measure exhaust oxygen content.

Q: Is it safe to drive with a P2248 code?

P2248 is a medium-severity code. Your vehicle may still be driveable in the short term, but you should avoid driving it for extended periods without repair. A malfunctioning upstream oxygen sensor can cause incorrect fuel trims, leading to poor fuel economy, rough running, and potential long-term damage to your catalytic converter, which is an expensive component to replace.

Q: Which oxygen sensor is Bank 2 Sensor 1?

Bank 2 Sensor 1 is the upstream (pre-catalytic converter) oxygen sensor located on the side of the engine that does NOT contain cylinder #1. On V6 and V8 engines, Bank 2 is typically the passenger side or driver side depending on the manufacturer and engine orientation — always consult a service manual or reliable online resource specific to your vehicle's year, make, and model to confirm the exact location.

Q: Can bad wiring cause a P2248 code instead of a bad sensor?

Yes — in many cases, P2248 is caused by wiring issues rather than a failed sensor. Damaged, melted, or corroded wiring near the exhaust manifold is a very common cause. Corroded connector terminals, a pinched harness, or a broken reference voltage wire between the PCM and the sensor can all trigger P2248 without the sensor itself being defective. Always inspect and test the wiring before replacing the sensor.

Q: How much does it cost to fix a P2248 code?

If the fix is a straightforward oxygen sensor replacement, you can expect to pay $20–$100 for the sensor part and $50–$150 in labor at a shop, for a total of $70–$250. If wiring repairs are needed, costs can increase to $150–$400 depending on the extent of the damage. PCM replacement is significantly more expensive, ranging from $500–$1,500 or more including programming, and should only be done after all other causes are ruled out.

Abstract

Error code P2248 indicates a problem with the heated oxygen sensor (HO2S) reference voltage performance on Bank 2, Sensor 1 — the upstream oxygen sensor on the engine side that does not contain cylinder #1. This means the PCM (Powertrain Control Module) has detected that the reference voltage signal from this sensor is outside the expected range, which can affect fuel trim calculations and emissions. Left unaddressed, this fault can reduce fuel economy, increase emissions, and potentially trigger catalytic converter damage over time.