AutoCodes – GMC – P22A7 2016 GMC Sierra

P22A7 2016 GMC Sierra Code - NOx Sensor 2 Heater Feedback Performance

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: P22A7 2016 GMC Sierra indicates NOx Sensor 2 Heater Feedback Performance.
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 163

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
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Code P22A7 2016 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 P22A7 2016 GMC Sierra - NOx Sensor 2 Heater Feedback Performance - AutoCodes.com — P22A7 2016 GMC Sierra Code - NOx Sensor 2 Heater Feedback Performance

What does this mean?

What are the Possible Causes of the DTC P22A7 2016 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 P22A7 2016 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 P22A7 2016 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 P22A7 2016 GMC Sierra code?

Need more information on how to fix the P22A7 2016 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P22A7 2016 GMC Sierra code diagnosed by a professional: Find a repair shop in your area

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 P22A7 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) in a 2016 GMC Sierra?

The common symptoms include reduced engine performance, decreased fuel efficiency, and the illumination of the check engine light.

2. What can cause the OBDII code P22A7 to trigger in a 2016 GMC Sierra?

The code P22A7 usually triggers due to a malfunction in the NOx Sensor 2 heater feedback system, which is responsible for monitoring and controlling emissions levels.

3. How serious is the OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) in a 2016 GMC Sierra?

While the vehicle may still be driveable with this code, it is important to address it promptly to prevent potential damage to the emissions system and ensure compliance with environmental regulations.

4. What are some possible DIY repair tips for fixing OBDII code P22A7 in a 2016 GMC Sierra?

DIY repair tips may include checking the wiring and connectors related to the NOx Sensor 2 heater, inspecting the sensor itself for any damage, and clearing the code with an OBDII scanner.

5. Can driving with the OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) cause further damage to the vehicle?

Continued driving with this code may lead to increased emissions, decreased fuel efficiency, and potential damage to other components of the emissions system over time.

6. How much does it typically cost to repair the OBDII code P22A7 in a 2016 GMC Sierra at a professional auto repair shop?

The cost of repairing the NOx Sensor 2 heater feedback performance issue can vary depending on the exact cause of the problem, but it may range from $200 to $500 or more including parts and labor.

7. Is it safe to reset the check engine light after addressing the OBDII code P22A7 in a 2016 GMC Sierra?

Yes, once the underlying issue triggering the code has been resolved, it is safe to reset the check engine light using an OBDII scanner to ensure the system recognizes the repair.

8. How can regular maintenance help prevent the recurrence of OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) in a 2016 GMC Sierra?

Regular maintenance, such as keeping the emissions system clean, replacing sensors at recommended intervals, and using quality fuel, can help prevent issues like P22A7 from reoccurring.

9. Is it possible for the OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) to resolve itself without any intervention in a 2016 GMC Sierra?

While intermittent issues may sometimes cause the code to disappear temporarily, it is not advisable to rely on self-resolution, as addressing the underlying problem is crucial for vehicle performance and emissions compliance.

10. What should I do if the OBDII code P22A7 (NOx Sensor 2 Heater Feedback Performance) persists in a 2016 GMC Sierra despite attempted repairs?

If the code persists after attempted repairs, it is recommended to seek the expertise of a professional mechanic or dealership to diagnose the issue accurately and prevent further complications.