AutoCodes – GMC – P22A3 2017 GMC Sierra

P22A3 2017 GMC Sierra Code - NOx Sensor 2 Heater Control Circuit

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: P22A3 2017 GMC Sierra indicates NOx Sensor 2 Heater Control Circuit.
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 273

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 P22A3 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 P22A3 2017 GMC Sierra - NOx Sensor 2 Heater Control Circuit - AutoCodes.com — P22A3 2017 GMC Sierra Code - NOx Sensor 2 Heater Control Circuit

What does this mean?

What are the Possible Causes of the DTC P22A3 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 P22A3 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 P22A3 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 P22A3 2017 GMC Sierra code?

Need more information on how to fix the P22A3 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P22A3 2017 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 P22A3 2017 GMC Sierra Code

1. What does the OBDII code P22A3 on a 2017 GMC Sierra indicate?

The code P22A3 indicates a problem with the NOx Sensor 2 Heater Control Circuit in a 2017 GMC Sierra.

2. What are common symptoms of a NOx Sensor 2 Heater Control Circuit issue in a GMC Sierra?

Common symptoms include poor engine performance, reduced fuel efficiency, and the illumination of the check engine light.

3. What are possible causes of the P22A3 OBDII code on a 2017 GMC Sierra?

Potential causes of the P22A3 code include a faulty NOx sensor, damaged wiring or connectors, or a malfunctioning heater control circuit.

4. How can I diagnose a NOx Sensor 2 Heater Control Circuit problem in my 2017 GMC Sierra?

Diagnosing this issue involves using an OBDII scanner to retrieve the specific trouble code, inspecting the sensor and related components for damage, and testing the circuit for proper voltage and continuity.

5. Can I continue driving my 2017 GMC Sierra with the P22A3 code present?

It is not recommended to continue driving with the P22A3 code active, as it can lead to increased emissions, reduced engine efficiency, and potential damage to other components.

6. Are there any simple repairs I can attempt for the NOx Sensor 2 Heater Control Circuit issue in my GMC Sierra?

Simple repairs may include checking and tightening sensor connections, replacing damaged wiring, or clearing the code to see if it reoccurs.

7. Should I replace the NOx sensor if I encounter the P22A3 code on my 2017 GMC Sierra?

If diagnostics point to the NOx sensor as the root cause of the issue, replacing it may be necessary to resolve the P22A3 code.

8. How much does it typically cost to repair a NOx Sensor 2 Heater Control Circuit problem in a 2017 GMC Sierra?

The cost of repair can vary depending on the exact cause of the issue, but it may range from a few hundred to over a thousand dollars, including parts and labor.

9. Can a DIY enthusiast fix the NOx Sensor 2 Heater Control Circuit problem in a 2017 GMC Sierra?

While some simple tasks like checking connections or replacing wiring may be manageable for a DIY enthusiast, diagnosing and repairing complex issues with the NOx sensor system may require professional expertise.

10. What are the potential long-term effects of ignoring the P22A3 code on a 2017 GMC Sierra?

Ignoring the P22A3 code can lead to increased emissions, potential damage to the catalytic converter, decreased engine efficiency, and ultimately, more costly repairs down the line.