AutoCodes – GMC – P22A0 2016 GMC Sierra

P22A0 2016 GMC Sierra Code - NOx Sensor 2 Circuit Low Voltage

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: P22A0 2016 GMC Sierra indicates NOx Sensor 2 Circuit Low Voltage.
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 339

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 P22A0 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 P22A0 2016 GMC Sierra - NOx Sensor 2 Circuit Low Voltage - AutoCodes.com — P22A0 2016 GMC Sierra Code - NOx Sensor 2 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P22A0 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 P22A0 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 P22A0 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 P22A0 2016 GMC Sierra code?

Need more information on how to fix the P22A0 2016 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P22A0 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 P22A0 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P22A0 in a 2016 GMC Sierra?

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

2. What does the OBDII code P22A0 indicating "NOx Sensor 2 Circuit Low Voltage" mean for a 2016 GMC Sierra?

- The code suggests that the NOx Sensor 2 in the vehicle is detecting a lower-than-normal voltage in its circuit.

3. What are some possible causes of the NOx Sensor 2 Circuit Low Voltage code in a 2016 GMC Sierra?

- Potential causes may include a faulty NOx sensor, damaged wiring or connectors, a failed sensor heater, or issues with the engine control module.

4. How can I diagnose the OBDII code P22A0 in my 2016 GMC Sierra?

- Diagnosis typically involves using an OBDII scanner to retrieve the code, inspecting the NOx sensor and its wiring for damage, and testing the sensor's voltage output.

5. Can I continue driving my 2016 GMC Sierra with the NOx Sensor 2 Circuit Low Voltage issue?

- It is generally not recommended to continue driving with this issue as it can lead to decreased engine efficiency and potential damage to the emissions system.

6. What are the repair options for fixing the NOx Sensor 2 Circuit Low Voltage problem in a 2016 GMC Sierra?

- Repair options may include replacing the faulty NOx sensor, repairing damaged wiring or connectors, checking and fixing the sensor heater, or reprogramming the engine control module.

7. Will resetting the check engine light resolve the P22A0 code in a 2016 GMC Sierra?

- Simply resetting the check engine light will not fix the underlying issue causing the code. It is essential to diagnose and repair the problem to prevent it from reoccurring.

8. How much does it typically cost to repair the NOx Sensor 2 Circuit Low Voltage issue in a 2016 GMC Sierra?

- The cost of repair can vary depending on the specific cause of the problem, but it may involve parts and labor expenses ranging from $200 to $600 or more.

9. Can a DIY enthusiast fix the NOx Sensor 2 Circuit Low Voltage problem in a 2016 GMC Sierra?

- While some experienced DIYers may be able to replace the NOx sensor or check wiring connections, diagnosing and repairing this issue often requires specialized tools and knowledge best handled by a professional mechanic.

10. How often does the NOx Sensor 2 Circuit Low Voltage issue occur in 2016 GMC Sierra vehicles?

- The occurrence of this specific code may vary, but it is not an uncommon problem in vehicles equipped with NOx sensors, especially as the vehicle ages. Regular maintenance and prompt repairs can help prevent such issues.