AutoCodes – GMC – P11D2 2014 GMC Sierra

P11D2 2014 GMC Sierra Code - O2 Signal Circuit High Voltage (NOx Sensor 2)

Quick Answer

The Nitrogen Oxides (NOx) sensors are part of the selective catalytic reduction system, a device used to reduce NOx emission on diesel engines. Common causes include Faulty Nitrogen Oxides (NOx) Sensor 2, Nitrogen Oxides Sensor 2 harness is open or shorted, Nitrogen Oxides 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: P11D2 2014 GMC Sierra indicates O2 Signal Circuit High Voltage (NOx Sensor 2).
Common causes: Common causes include Faulty Nitrogen Oxides (NOx) Sensor 2, Nitrogen Oxides Sensor 2 harness is open or shorted, Nitrogen Oxides 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 214

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Mar 24, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P11D2 2014 GMC Sierra Description

The Nitrogen Oxides (NOx) sensors are part of the selective catalytic reduction system, a device used to reduce NOx emission on diesel engines. There are two NOx sensors, one placed upstream of selective catalytic reduction, to measure inlet NOx concentration, and one placed downstream. They are connected with the control module via CAN and all the information is exchanged through it. Since it is a smart sensor, all the electrical monitoring is performed inside the sensor and only the results are sent to the Engine Control Module (ECM). Each NOx sensor contains a sensing cell, a pumping cell, and a heater. A sample of exhaust gas passes through a diffusion gap between the sensing cell and the pumping cell. The NOx sensor maintains a constant reference voltage across the sensing cell. An electronic circuit within the sensor controls the pump current through the pumping cell in order to maintain a constant voltage in the sensing cell. The amount of current required to maintain the reference voltage in the sensing cell is proportional to the concentration of NOx in the exhaust. The ECM varies the amount of diesel exhaust fluid (reductant) added by varying the reductant injector duty cycle in response to changes in engine exhaust NOx levels. The smart NOx sensors consist of two components, the NOx module and the NOx sensor element that are serviced as a unit. A circuit or performance condition with a NOx sensor is detected by the NOx sensor module. The smart NOx sensor module communicates the condition to the ECM over the serial data line. The ECM sets a DTC when a serial data message is received from the NOx sensor module. The Diagnostic Trouble Code (DTC) will be set if the ECM software detects a fault in the NOx sensor circuitry or a performance fault in the NOx sensor for greater than 2 s.

OBDII Code P11D2 2014 GMC Sierra - O2 Signal Circuit High Voltage (NOx Sensor 2) - AutoCodes.com — P11D2 2014 GMC Sierra Code - O2 Signal Circuit High Voltage (NOx Sensor 2)

What does this mean?

What are the Possible Causes of the DTC P11D2 2014 GMC Sierra?

Faulty Nitrogen Oxides (NOx) Sensor 2
Nitrogen Oxides Sensor 2 harness is open or shorted
Nitrogen Oxides Sensor 2 circuit poor electrical connection

How to Fix the DTC P11D2 2014 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P11D2 2014 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.

Need more information about the P11D2 2014 GMC Sierra code?

Need more information on how to fix the P11D2 2014 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

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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 P11D2 2014 GMC Sierra Code

1. What are the common symptoms of OBDII code P11D2 in a 2014 GMC Sierra related to the O2 Signal Circuit High Voltage (NOx Sensor 2)?

The common symptoms of P11D2 may include poor fuel economy, engine misfires, rough idling, and possibly an illuminated Check Engine light.

2. What are the typical causes of OBDII code P11D2 in a 2014 GMC Sierra?

Common causes of P11D2 can include a faulty NOx sensor, wiring issues in the O2 signal circuit, a malfunctioning PCM, or issues with the exhaust system.

3. How serious is OBDII code P11D2 in a 2014 GMC Sierra?

While P11D2 may not cause immediate harm to your vehicle, it can lead to poor engine performance and increased emissions. It is advisable to address this issue promptly to prevent further damage.

4. Can I continue driving my 2014 GMC Sierra with OBDII code P11D2 present?

It is not recommended to drive your vehicle for an extended period with P11D2 unresolved. Continuing to drive with this code may result in decreased fuel efficiency and potential long-term damage to the engine or emissions system.

5. How can I diagnose and repair OBDII code P11D2 in my 2014 GMC Sierra?

To diagnose and repair P11D2, it is recommended to use an OBDII scanner to pinpoint the exact cause. Inspect the NOx sensor, check the wiring for any damage, and test the PCM for proper functioning. Repair or replace components as needed.

6. Is it possible to reset OBDII code P11D2 in a 2014 GMC Sierra without fixing the underlying issue?

While you can clear the code temporarily by resetting the PCM, the Check Engine light is likely to reappear if the root cause of P11D2 is not addressed. It is best to fix the underlying issue to prevent further problems.

7. Can weather conditions affect OBDII code P11D2 in a 2014 GMC Sierra?

Extreme weather conditions, such as excessive heat or moisture, can potentially impact the performance of the NOx sensor and trigger P11D2. Ensure proper insulation and protection for the sensor in such conditions.

8. How much does it typically cost to repair OBDII code P11D2 in a 2014 GMC Sierra?

The cost of repairing P11D2 can vary depending on the exact cause of the issue. Repairs may range from replacing a sensor or fixing wiring to addressing more complex PCM problems. It is advisable to consult a mechanic for an accurate estimate.

9. Can a DIY enthusiast with basic automotive knowledge fix OBDII code P11D2 in a 2014 GMC Sierra?

While some aspects of diagnosing and repairing P11D2 may be within reach for DIY enthusiasts, complex issues like PCM malfunctions may require professional expertise. It is recommended to assess your comfort level and seek assistance if needed.

10. How often does OBDII code P11D2 occur in a 2014 GMC Sierra, and is it a common issue?

P11D2 related to the O2 Signal Circuit High Voltage (NOx Sensor 2) may not be as common as some other OBDII codes but can still occur in 2014 GMC Sierra models. Regular maintenance and prompt attention to any warning lights can help prevent such issues.