AutoCodes – Hyundai – P2256 Hyundai

P2256 Hyundai Code - O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1

Quick Answer

The Front Oxygen Sensor (O2 Sensor 1) is placed into the exhaust manifold. Common causes include Faulty Front Oxygen Sensor Bank 2, Front Oxygen Sensor Bank 2 harness is open or shorted, Front Oxygen Sensor Bank 2 circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means: P2256 Hyundai indicates O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1.
Common causes: Common causes include Faulty Front Oxygen Sensor Bank 2, Front Oxygen Sensor Bank 2 harness is open or shorted, Front Oxygen Sensor Bank 2 circuit poor electrical connection.
Severity: Moderate - service should be scheduled soon.
Can I drive?: The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,377

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P2256 Hyundai Description

The Front Oxygen Sensor (O2 Sensor 1) is placed into the exhaust manifold. It detects the amount of oxygen in the exhaust gas compared to the outside air. The heated oxygen sensor 1 has a closed-end tube made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. The heated oxygen sensor 1 signal is sent to the Engine Control Module (ECM). The ECM adjusts the injection pulse duration to achieve the ideal air-fuel ratio. The ideal air-fuel ratio occurs near the radical change from 1V to 0V.

OBDII Code P2256 Hyundai - O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1 - AutoCodes.com — P2256 Hyundai Code - O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1

What does this mean?

What are the Possible Causes of the DTC P2256 Hyundai?

Faulty Front Oxygen Sensor Bank 2
Front Oxygen Sensor Bank 2 harness is open or shorted
Front Oxygen Sensor Bank 2 circuit poor electrical connection

How to Fix the DTC P2256 Hyundai?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2256 Hyundai code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P2256 Hyundai code?

Need more information on how to fix the P2256 Hyundai code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P2256 Hyundai code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P2256 Hyundai Code

What does OBDII code P2256 mean on a Hyundai?

1. P2256 indicates an issue with the O2 Sensor Negative Current Control Circuit High for Bank 2 Sensor 1. This means the sensor is detecting an abnormally high current in the circuit. 2.

What are the common symptoms of P2256 in a Hyundai?

Symptoms may include poor fuel efficiency, rough idling, an illuminated check engine light, and potential engine performance issues. 3.

What causes the P2256 code to appear in a Hyundai?

Common causes include a faulty oxygen sensor, damaged wiring or connectors in the O2 sensor circuit, a malfunctioning PCM (Powertrain Control Module), or exhaust leaks near the sensor. 4.

Which oxygen sensor does P2256 refer to in a Hyundai?

P2256 refers to the upstream oxygen sensor (Sensor 1) on Bank 2, which is the side of the engine opposite the #1 cylinder. 5.

Can a bad O2 sensor trigger the P2256 code in a Hyundai?

Yes, a defective oxygen sensor is one of the most common reasons for the P2256 code to appear. 6.

How is the P2256 code diagnosed in a Hyundai?

A mechanic will typically use an OBDII scanner to confirm the code, inspect the wiring and connectors for damage, and test the oxygen sensor's operation using a multimeter or oscilloscope. 7.

Can I drive my Hyundai with the P2256 code active?

While it may be possible to drive, it's not recommended as it could lead to further engine damage, poor performance, and increased emissions. 8.

How do you fix the P2256 code on a Hyundai?

Repairs may include replacing the faulty oxygen sensor, repairing or replacing damaged wiring or connectors, fixing exhaust leaks, or reprogramming/updating the PCM if needed. 9.

How much does it cost to fix the P2256 code in a Hyundai?

The cost varies depending on the repair, but replacing an oxygen sensor typically costs $150â€“$300, while wiring repairs or PCM updates may cost more. 10.

Can a dirty air filter cause the P2256 code in a Hyundai?

A dirty air filter is unlikely to directly cause P2256, but it can contribute to poor engine performance, which may indirectly affect sensor readings.