AutoCodes – GMC – P11DA GMC

P11DA GMC Code - O2 Pump Current Control 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: P11DA GMC indicates O2 Pump Current Control 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.

Save to My Repairs My Repairs

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

Code Popularity 451

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 24, 2024

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 P11DA GMC 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 P11DA GMC - O2 Pump Current Control Circuit High Voltage (NOx Sensor 2) - AutoCodes.com — P11DA GMC Code - O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)

What does this mean?

What are the Possible Causes of the DTC P11DA GMC?

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 P11DA GMC?

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 P11DA GMC 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 P11DA GMC code?

Need more information on how to fix the P11DA GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P11DA GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P11DA 2014 GMC Sierra — O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)
P11DA 2015 GMC Sierra — O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)
P11DA 2016 GMC Sierra — O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)
P11DA 2017 GMC Sierra — O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)
P11DA 2018 GMC Sierra — O2 Pump Current Control Circuit High Voltage (NOx Sensor 2)

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 P11DA GMC Code

What does the OBDII code P11DA mean for my GMC vehicle?

The OBDII code P11DA indicates a high voltage condition in the O2 pump current control circuit related to the NOx sensor 2, which can affect emissions performance.

What are the common symptoms of the P11DA code?

Common symptoms include increased emissions, poor fuel economy, rough idle, engine performance issues, and the check engine light being illuminated.

What could cause the P11DA code to trigger?

Causes may include a faulty NOx sensor 2, issues with the wiring or connectors in the O2 pump control circuit, or a malfunctioning engine control module (ECM).

Can I drive my vehicle with the P11DA code?

While you may be able to drive the vehicle, itâ€™s not advisable as it can lead to increased emissions and potential damage to the engine or exhaust system over time.

How can I diagnose the P11DA code?

Begin by using an OBDII scanner to read the code, then visually inspect the wiring and connectors for damage, and check the operation of the NOx sensor 2 with a multimeter.

What repairs are typically needed for the P11DA code?

Repairs may involve replacing the NOx sensor 2, repairing or replacing damaged wiring or connectors, or addressing issues with the ECM if it is not functioning correctly.

Will clearing the P11DA code fix the problem?

Clearing the code may temporarily turn off the check engine light, but the underlying issue must be resolved to prevent the code from reappearing.

How can I prevent the P11DA code from returning?

Regular maintenance, such as checking and replacing faulty sensors, ensuring proper electrical connections, and keeping the exhaust system in good condition, can help prevent the code from returning.

Is the P11DA code serious?

Yes, it can be serious as it affects the emissions system and could lead to increased pollution and potential failures during emissions testing. It's recommended to address the issue promptly.