AutoCodes – GMC – P0056 2015 GMC Sierra

P0056 2015 GMC Sierra Code - HO2S Heater Control Circuit Bank 2 Sensor 2

Quick Answer

Heated Oxygen Sensors (HO2S) are used for fuel control and post catalyst monitoring. Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 2, Heated Oxygen Sensor Bank 2 Sensor 2 harness is open shorted, Heated Oxygen Sensor Bank 2 Sensor 2 circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0056 2015 GMC Sierra indicates HO2S Heater Control Circuit Bank 2 Sensor 2.
Common causes: Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 2, Heated Oxygen Sensor Bank 2 Sensor 2 harness is open shorted, Heated Oxygen Sensor Bank 2 Sensor 2 circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 293

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 25, 2024

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0056 2015 GMC Sierra Description

Heated Oxygen Sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach an operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensors to reach operating temperature. Voltage is provided to the heater by an ignition voltage circuit through a fuse. With the engine running, the ground is provided to the heater by the HO2S heater low control circuit through a low side driver within the Engine Control Module (ECM). The ECM uses Pulse Width Modulation (PWM) to control the HO2S heater operation to maintain a specific HO2S operating temperature range.
The Diagnostic Trouble Code (DTC) will be set when the ECM detects an open circuit in the heater output low side driver circuit of the heated oxygen sensor when the heater is commanded OFF for greater than 5 s.

OBDII Code P0056 2015 GMC Sierra - HO2S Heater Control Circuit Bank 2 Sensor 2 - AutoCodes.com — P0056 2015 GMC Sierra Code - HO2S Heater Control Circuit Bank 2 Sensor 2

What does this mean?

What are the Possible Causes of the DTC P0056 2015 GMC Sierra?

Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 2
Heated Oxygen Sensor Bank 2 Sensor 2 harness is open shorted
Heated Oxygen Sensor Bank 2 Sensor 2 circuit poor electrical connection
Heated Oxygen Sensor Bank 2 Sensor 2 circuit fuse
Faulty Engine Control Module (ECM)

How to Fix the DTC P0056 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

The code means that there is a problem with the heater element circuit of the heated oxygen sensor. The control module monitors how long it takes the sensor to warm up and start sending an adequate signal. The code is set when the sensor is taking too long to warm up. Water getting inside the heated oxygen sensor connector can cause the heated oxygen sensor fuse to blow. Before replacing the sensor, check for the condition of the heated oxygen sensor fuse and connectors. If the fuse and connector are OK, replacing the O2 Sensor usually takes care of the problem.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0056 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 P0056 2015 GMC Sierra Code

1. What does OBDII code P0056 on a 2015 GMC Sierra mean?

The code P0056 indicates a malfunction in the HO2S (Heated Oxygen Sensor) heater control circuit for Bank 2 Sensor 2.

2. What are the common symptoms of OBDII code P0056 in a 2015 GMC Sierra?

Common symptoms of P0056 may include poor fuel economy, rough idling, reduced engine performance, and an illuminated check engine light.

3. What are the possible causes of OBDII code P0056 on a 2015 GMC Sierra?

Potential causes of P0056 include a faulty oxygen sensor, damaged wiring or connectors, a blown fuse, or a problem with the engine control module (ECM).

4. How can I diagnose the OBDII code P0056 on my 2015 GMC Sierra?

Diagnosing P0056 typically involves checking the oxygen sensor heater circuit for continuity, inspecting the wiring and connectors for damage, and testing the sensor's resistance.

5. Can I continue driving my 2015 GMC Sierra with the OBDII code P0056?

It's not recommended to drive with an unresolved P0056 code as it can lead to decreased fuel efficiency and potential long-term damage to the vehicle's emissions system.

6. How do I repair OBDII code P0056 on my 2015 GMC Sierra?

Repairing P0056 may involve replacing the Bank 2 Sensor 2 oxygen sensor, repairing damaged wiring or connectors, checking and replacing fuses if necessary, and clearing the trouble code.

7. Are there any DIY tips for fixing OBDII code P0056 on a 2015 GMC Sierra?

While some basic diagnostic steps can be performed by DIY enthusiasts, it's recommended to consult a professional technician for a thorough diagnosis and repair of the issue.

8. How much does it cost to fix OBDII code P0056 on a 2015 GMC Sierra?

The cost of repairing P0056 can vary depending on the specific issue, parts needed, and labor rates. It's advisable to obtain quotes from local auto repair shops for accurate pricing.

9. Will resetting the check engine light resolve OBDII code P0056 on a 2015 GMC Sierra?

Simply resetting the check engine light without addressing the underlying issue causing P0056 will not solve the problem. It's essential to diagnose and repair the root cause of the code.

10. How can I prevent OBDII code P0056 from appearing on my 2015 GMC Sierra in the future?

Regular maintenance, such as checking and replacing oxygen sensors at recommended intervals, inspecting wiring for damage, and addressing any engine performance issues promptly, can help prevent the recurrence of P0056.