AutoCodes – GMC – P2271 2015 GMC Sierra

P2271 2015 GMC Sierra Code - HO2S Signal Stuck Rich Bank 1 Sensor 2

Quick Answer

The Heated Oxygen Sensors (HO2S) are used for fuel control and catalyst monitoring. Common causes include Faulty Heated Oxygen Bank 1 Sensor 2, Heated Oxygen Bank 1 Sensor 2 harness is open or shorted, Heated Oxygen Bank 1 Sensor 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: P2271 2015 GMC Sierra indicates HO2S Signal Stuck Rich Bank 1 Sensor 2.
Common causes: Common causes include Faulty Heated Oxygen Bank 1 Sensor 2, Heated Oxygen Bank 1 Sensor 2 harness is open or shorted, Heated Oxygen Bank 1 Sensor 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.

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Code Popularity 322

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 May 28, 2022

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code P2271 2015 GMC Sierra Description

The Heated Oxygen Sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream. When the engine is started, the Engine Control Module (ECM) operates in an Open Loop mode, ignoring the HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a range of 0 - 1, 000 mV. Once sufficient HO2S voltage fluctuation is observed by the ECM, Closed Loop is entered. The ECM uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1, 000 mV indicates a rich fuel mixture. An HO2S voltage that decreases toward 0 mV indicates a lean fuel mixture.
The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed Loop earlier and the ECM to calculate the air-to-fuel ratio sooner.
The Diagnostic Trouble Code (DTC) will be set when the ECM does not detect an HO2S voltage less than 100 mV before accumulated mass airflow exceeds a calibrated value.

OBDII Code P2271 2015 GMC Sierra - HO2S Signal Stuck Rich Bank 1 Sensor 2 - AutoCodes.com — P2271 2015 GMC Sierra Code - HO2S Signal Stuck Rich Bank 1 Sensor 2

What does this mean?

What are the Possible Causes of the DTC P2271 2015 GMC Sierra?

Faulty Heated Oxygen Bank 1 Sensor 2
Heated Oxygen Bank 1 Sensor 2 harness is open or shorted
Heated Oxygen Bank 1 Sensor 2 circuit poor electrical connection
Low or high fuel system pressure
Fuel contamination
Faulty fuel injectors
Exhaust gas leaks
Engine vacuum leaks

How to Fix the DTC P2271 2015 GMC Sierra?

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 does this mean?

Code Tech Notes

Replacing the Rear Heated Oxygen Sensors (HO2S) usually takes care of the problem.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2271 2015 GMC Sierra 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.

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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 P2271 2015 GMC Sierra Code

1. What are the common symptoms of OBDII code P2271 in a 2015 GMC Sierra?

The common symptoms of code P2271 "HO2S Signal Stuck Rich Bank 1 Sensor 2" in a 2015 GMC Sierra may include poor fuel economy, rough idling, engine hesitation, and an illuminated Check Engine Light.

2. What does the OBDII code P2271 "HO2S Signal Stuck Rich Bank 1 Sensor 2" mean?

OBDII code P2271 indicates that the oxygen sensor (HO2S) signal for Bank 1 Sensor 2 is detecting a consistently rich air-fuel mixture condition in a 2015 GMC Sierra.

3. What are the possible causes of OBDII code P2271 in a 2015 GMC Sierra?

Possible causes of code P2271 in a 2015 GMC Sierra include a faulty oxygen sensor, fuel pressure regulator issues, vacuum leaks, exhaust system leaks, or a malfunctioning engine control module (ECM).

4. How can I diagnose OBDII code P2271 in my 2015 GMC Sierra?

Diagnosing code P2271 involves using an OBDII scanner to retrieve the code, inspecting the oxygen sensor and its wiring, checking for vacuum leaks, examining the exhaust system, and testing the fuel pressure regulator.

5. Can I drive my 2015 GMC Sierra with OBDII code P2271?

It is not recommended to drive your 2015 GMC Sierra with code P2271 for an extended period. While the vehicle may still be operable, driving with a rich air-fuel mixture can lead to poor performance and potential damage to the engine components.

6. How do I repair OBDII code P2271 in my 2015 GMC Sierra?

Repairing code P2271 may involve replacing the Bank 1 Sensor 2 oxygen sensor, fixing any vacuum leaks, addressing exhaust system leaks, checking the fuel pressure regulator, and resetting the ECM after completing the repairs.

7. Can a dirty air filter cause OBDII code P2271 in a 2015 GMC Sierra?

A dirty air filter is not a direct cause of code P2271. While a dirty air filter can affect engine performance, the code is specifically related to the oxygen sensor detecting a rich air-fuel mixture condition.

8. How much does it cost to fix OBDII code P2271 in a 2015 GMC Sierra?

The cost to fix code P2271 in a 2015 GMC Sierra can vary depending on the specific cause of the issue. Repairs may range from a few hundred dollars for an oxygen sensor replacement to more significant costs if other components need attention.

9. Will resetting the Check Engine Light resolve OBDII code P2271 in a 2015 GMC Sierra?

Simply resetting the Check Engine Light will not resolve code P2271 in a 2015 GMC Sierra. It is important to diagnose the underlying issue causing the rich air-fuel mixture condition and perform the necessary repairs to clear the code.

10. How long does it take to repair OBDII code P2271 in a 2015 GMC Sierra?

The time to repair code P2271 in a 2015 GMC Sierra can vary based on the specific cause and complexity of the issue. Simple fixes like replacing an oxygen sensor may take a few hours, while more involved repairs could require a day or more.