AutoCodes – Chevrolet – P22A1 2017 Chevrolet Silverado

P22A1 2017 Chevrolet Silverado Code - NOx Sensor 2 Circuit High 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: P22A1 2017 Chevrolet Silverado indicates NOx Sensor 2 Circuit High 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 222

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 P22A1 2017 Chevrolet Silverado 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 P22A1 2017 Chevrolet Silverado - NOx Sensor 2 Circuit High Voltage - AutoCodes.com — P22A1 2017 Chevrolet Silverado Code - NOx Sensor 2 Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P22A1 2017 Chevrolet Silverado?

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 P22A1 2017 Chevrolet Silverado?

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 P22A1 2017 Chevrolet Silverado 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 P22A1 2017 Chevrolet Silverado code?

Need more information on how to fix the P22A1 2017 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P22A1 2017 Chevrolet Silverado 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 P22A1 2017 Chevrolet Silverado Code

1. What does the OBDII code P22A1 mean on a 2017 Chevrolet Silverado?

P22A1 indicates a high voltage issue in the circuit of NOx Sensor 2, which monitors nitrogen oxide levels in the exhaust system downstream of the catalytic converter.

2. What are the symptoms of code P22A1 on a 2017 Chevrolet Silverado?

Common symptoms include the Check Engine Light turning on, reduced fuel efficiency, poor engine performance, and, in some cases, the vehicle entering limp mode.

3. What causes the P22A1 code on a 2017 Chevrolet Silverado?

Possible causes include a faulty NOx Sensor 2, damaged wiring or connectors in the sensor's circuit, excessive exhaust soot buildup, or issues with the vehicle's ECM.

4. Can a dirty exhaust system cause the P22A1 code?

Yes, excessive soot or carbon buildup in the exhaust system can interfere with NOx Sensor 2 readings and trigger this code.

5. How do I diagnose the P22A1 code on my Silverado?

Start by visually inspecting the wiring and connectors for damage or corrosion. Use a scan tool to monitor NOx Sensor 2 voltage and compare it to specifications. If necessary, test or replace the sensor.

6. Can I drive my 2017 Chevrolet Silverado with a P22A1 code?

Itâ€™s not recommended to drive for extended periods with this code active, as it can lead to reduced performance and potential damage to the exhaust or emissions system.

7. How much does it cost to fix the P22A1 code on a 2017 Chevrolet Silverado?

Repair costs can vary, but replacing the NOx sensor typically ranges from $300 to $600, including parts and labor. Wiring repairs may cost less.

8. Does the P22A1 code affect emissions testing?

Yes, since the NOx sensor is part of the emissions control system, this code will likely cause your Silverado to fail an emissions test.

9. How can I prevent the P22A1 code from recurring?

Regular maintenance, such as cleaning the exhaust system and inspecting wiring, can help prevent future issues with the NOx sensor.

10. Is it necessary to replace NOx Sensor 2 to fix the P22A1 code?

Not always. Sometimes the issue is due to wiring problems or a temporary fault. Diagnosing the circuit thoroughly can help determine if the sensor itself needs replacement.