AutoCodes – GMC – P22A5 2018 GMC Sierra

P22A5 2018 GMC Sierra Code - NOx Sensor 2 Heater Control 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: P22A5 2018 GMC Sierra indicates NOx Sensor 2 Heater Control 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 152

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 P22A5 2018 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 P22A5 2018 GMC Sierra - NOx Sensor 2 Heater Control Circuit High Voltage - AutoCodes.com — P22A5 2018 GMC Sierra Code - NOx Sensor 2 Heater Control Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P22A5 2018 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 P22A5 2018 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 P22A5 2018 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 P22A5 2018 GMC Sierra code?

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Need Help with the Code?

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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 P22A5 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P22A5 in a 2018 GMC Sierra related to NOx Sensor 2 Heater Control Circuit High Voltage?

The common symptoms include illuminated check engine light, reduced engine performance, and potential failed emissions test.

2. What are the possible causes of OBDII code P22A5 in a 2018 GMC Sierra indicating a NOx Sensor 2 Heater Control Circuit High Voltage issue?

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

3. How serious is the OBDII code P22A5 in a 2018 GMC Sierra related to NOx Sensor 2 Heater Control Circuit High Voltage?

While the vehicle may still operate, it is important to address this issue promptly as it can affect the vehicle's emissions output and overall performance.

4. How can I diagnose the OBDII code P22A5 in a 2018 GMC Sierra linked to NOx Sensor 2 Heater Control Circuit High Voltage?

Diagnosis typically involves using a diagnostic scanner to retrieve the trouble codes, inspecting the wiring and connectors, testing the sensor's resistance, and checking the heater control circuit.

5. Can I continue driving my 2018 GMC Sierra with the OBDII code P22A5 NOx Sensor 2 Heater Control Circuit High Voltage issue?

While it may be possible to continue driving, it is recommended to address the problem promptly to prevent potential damage to other components and ensure proper emissions compliance.

6. How can I repair the OBDII code P22A5 in my 2018 GMC Sierra associated with NOx Sensor 2 Heater Control Circuit High Voltage?

Repair options may include replacing the faulty NOx sensor, repairing or replacing damaged wiring/connectors, addressing issues with the heater control circuit, or reprogramming the engine control module.

7. Are there any DIY tips for addressing the OBDII code P22A5 in a 2018 GMC Sierra related to NOx Sensor 2 Heater Control Circuit High Voltage?

While basic inspections and checks can be done by DIY enthusiasts, it is recommended to consult a professional mechanic for a proper diagnosis and repair of this complex issue.

8. How much does it typically cost to repair the OBDII code P22A5 NOx Sensor 2 Heater Control Circuit High Voltage in a 2018 GMC Sierra?

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

9. Can resetting the OBDII system clear the P22A5 code in a 2018 GMC Sierra with a NOx Sensor 2 Heater Control Circuit High Voltage problem?

Resetting the system may clear the code temporarily, but if the underlying issue is not addressed, the code is likely to reappear once the vehicle is driven and the system performs its diagnostic checks.

10. How soon should I address the OBDII code P22A5 in my 2018 GMC Sierra indicating NOx Sensor 2 Heater Control Circuit High Voltage issues?

It is recommended to address the issue as soon as possible to prevent potential damage to other components, ensure proper emissions compliance, and maintain optimal vehicle performance.