AutoCodes – GMC – P11D8 2017 GMC Sierra

P11D8 2017 GMC Sierra Code - O2 Pump Current Control Circuit (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: P11D8 2017 GMC Sierra indicates O2 Pump Current Control Circuit (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 287

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 P11D8 2017 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 P11D8 2017 GMC Sierra - O2 Pump Current Control Circuit (NOx Sensor 2) - AutoCodes.com — P11D8 2017 GMC Sierra Code - O2 Pump Current Control Circuit (NOx Sensor 2)

What does this mean?

What are the Possible Causes of the DTC P11D8 2017 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 P11D8 2017 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 P11D8 2017 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 P11D8 2017 GMC Sierra code?

Need more information on how to fix the P11D8 2017 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 P11D8 2017 GMC Sierra Code

1. What are the common symptoms of OBDII code P11D8 in a 2017 GMC Sierra?

- Common symptoms include decreased fuel efficiency, rough idling, and the illumination of the check engine light.

2. What does the O2 Pump Current Control Circuit (NOx Sensor 2) code P11D8 indicate in a 2017 GMC Sierra?

- This code indicates a malfunction in the oxygen pump current control circuit of the NOx sensor 2 in the vehicle's exhaust system.

3. What are the possible causes of OBDII code P11D8 in a 2017 GMC Sierra?

- Possible causes include a faulty oxygen pump, damaged wiring or connectors in the circuit, or a malfunctioning NOx sensor 2.

4. How can I diagnose the O2 Pump Current Control Circuit (NOx Sensor 2) code P11D8 in my 2017 GMC Sierra?

- Diagnosing this code typically involves inspecting the oxygen pump, checking the circuit for any damage, and testing the NOx sensor 2 for proper functionality.

5. Can driving with OBDII code P11D8 in a 2017 GMC Sierra cause further damage?

- Continuing to drive with this code may lead to decreased engine performance and potential damage to other components of the exhaust system.

6. How can I repair OBDII code P11D8 in my 2017 GMC Sierra?

- Repairing this code often involves replacing the faulty oxygen pump, repairing any damaged wiring or connectors, or replacing the malfunctioning NOx sensor 2.

7. Is it safe to continue driving my 2017 GMC Sierra with the check engine light on due to code P11D8?

- It is not recommended to drive with the check engine light on, as the underlying issue causing the code may worsen over time and lead to additional problems.

8. How much does it typically cost to repair OBDII code P11D8 in a 2017 GMC Sierra?

- The cost of repairing this code can vary depending on the specific cause, but it may range from a couple of hundred dollars to over a thousand dollars for parts and labor.

9. Can I reset the check engine light after repairing OBDII code P11D8 in my 2017 GMC Sierra?

- Yes, once the underlying issue causing the code has been repaired, the check engine light can be reset using an OBDII scanner to clear the code.

10. How often does OBDII code P11D8 occur in a 2017 GMC Sierra?

- While not extremely common, this code can occur due to various factors such as age, mileage, and driving conditions, so it's important to address it promptly when it does appear.