AutoCodes – Chevrolet – P22A4 2014 Chevrolet Silverado

P22A4 2014 Chevrolet Silverado Code - NOx Sensor 2 Heater Control 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: P22A4 2014 Chevrolet Silverado indicates NOx Sensor 2 Heater Control 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 241

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 P22A4 2014 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 P22A4 2014 Chevrolet Silverado - NOx Sensor 2 Heater Control Circuit Low Voltage - AutoCodes.com — P22A4 2014 Chevrolet Silverado Code - NOx Sensor 2 Heater Control Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P22A4 2014 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 P22A4 2014 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 P22A4 2014 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 P22A4 2014 Chevrolet Silverado code?

Need more information on how to fix the P22A4 2014 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P22A4 2014 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 P22A4 2014 Chevrolet Silverado Code

1. What are the common symptoms of OBDII code P22A4 in a 2014 Chevrolet Silverado?

- Common symptoms include the check engine light turning on, reduced engine performance, increased fuel consumption, and potential exhaust emissions issues.

2. What does the OBDII code P22A4 NOx Sensor 2 Heater Control Circuit Low Voltage indicate?

- This code indicates a low voltage condition in the heater control circuit of the NOx sensor 2 in the exhaust system of the vehicle.

3. What are the possible causes of the NOx Sensor 2 Heater Control Circuit Low Voltage code in a 2014 Chevrolet Silverado?

- Possible causes include a faulty NOx sensor, damaged wiring or connectors in the heater circuit, a blown fuse, or issues with the vehicle's engine control module.

4. How can I diagnose the cause of the P22A4 code in my 2014 Chevrolet Silverado?

- Diagnosing the issue may require using an OBDII scanner to retrieve the specific fault codes, inspecting the NOx sensor and its wiring for damage, and testing the heater circuit for continuity and proper voltage.

5. Can I continue to drive my Chevrolet Silverado with the P22A4 code present?

- It is generally not recommended to drive the vehicle with this code present, as it can lead to decreased fuel efficiency, engine performance issues, and potential harm to the environment.

6. How can I repair the NOx Sensor 2 Heater Control Circuit Low Voltage issue in my 2014 Chevrolet Silverado?

- Repairing the issue may involve replacing the faulty NOx sensor, repairing or replacing damaged wiring or connectors, checking and replacing any blown fuses, and clearing the fault codes.

7. Is it possible to reset the P22A4 code in a 2014 Chevrolet Silverado without making any repairs?

- While you can clear the code with an OBDII scanner, it is recommended to diagnose and repair the underlying issue causing the fault code to prevent it from reoccurring.

8. Can a DIY enthusiast fix the NOx Sensor 2 Heater Control Circuit Low Voltage problem in a 2014 Chevrolet Silverado?

- Depending on your skill level and access to tools, a DIY enthusiast may be able to diagnose and repair this issue, but it is recommended to seek professional help if unsure.

9. How much does it typically cost to repair the P22A4 code in a 2014 Chevrolet Silverado at a repair shop?

- Repair costs can vary depending on the exact cause of the issue, but it may range from $200 to $500 or more, including parts and labor.

10. Are there any preventative maintenance steps I can take to avoid encountering the P22A4 code in my 2014 Chevrolet Silverado?

- Regularly checking and maintaining the vehicle's exhaust system, ensuring proper engine performance and fuel quality, and addressing any warning lights promptly can help prevent issues leading to this fault code.