AutoCodes – GMC – P119F 2018 GMC Sierra

P119F 2018 GMC Sierra Code - NOx Sensor 2 Signal 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: P119F 2018 GMC Sierra indicates NOx Sensor 2 Signal 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 208

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 P119F 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 P119F 2018 GMC Sierra - NOx Sensor 2 Signal Circuit High Voltage - AutoCodes.com — P119F 2018 GMC Sierra Code - NOx Sensor 2 Signal Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P119F 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 P119F 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 P119F 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 P119F 2018 GMC Sierra 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 P119F 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P119F in a 2018 GMC Sierra related to NOx Sensor 2 Signal Circuit High Voltage?

The common symptoms include reduced engine performance, decreased fuel efficiency, and the illumination of the Check Engine Light.

2. What are the possible causes of OBDII code P119F in a 2018 GMC Sierra indicating NOx Sensor 2 Signal Circuit High Voltage?

Potential causes include a faulty NOx sensor, damaged wiring or connectors in the sensor circuit, issues with the engine control module (ECM), or exhaust system problems.

3. How can I diagnose the NOx Sensor 2 Signal Circuit High Voltage issue in my 2018 GMC Sierra triggering code P119F?

Diagnosis involves using an OBDII scanner to retrieve the trouble code, inspecting the NOx sensor and related wiring for damage, and testing the sensor's voltage output using a multimeter.

4. Is it safe to continue driving my 2018 GMC Sierra with OBDII code P119F related to NOx Sensor 2 Signal Circuit High Voltage?

It is not recommended to drive the vehicle with this code active, as it can lead to further damage to the engine or emissions system. Prompt diagnosis and repair are advised.

5. Can I reset the Check Engine Light caused by OBDII code P119F in my 2018 GMC Sierra without fixing the underlying NOx Sensor 2 Signal Circuit High Voltage issue?

While you can clear the code temporarily, the Check Engine Light is likely to come back on until the root cause of the problem is addressed and resolved.

6. What are the repair options for fixing OBDII code P119F in a 2018 GMC Sierra due to NOx Sensor 2 Signal Circuit High Voltage?

Repair options include replacing the NOx sensor, repairing damaged wiring or connectors, reprogramming the ECM, or addressing any exhaust system issues that may be contributing to the problem.

7. Can a DIY enthusiast fix OBDII code P119F related to NOx Sensor 2 Signal Circuit High Voltage in a 2018 GMC Sierra?

Depending on the underlying cause, some DIY enthusiasts with the necessary tools and knowledge may be able to address this issue themselves, but professional diagnosis and repair are recommended for best results.

8. How much does it typically cost to repair OBDII code P119F in a 2018 GMC Sierra associated with NOx Sensor 2 Signal Circuit High Voltage?

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

9. Are there any preventative maintenance tips to avoid OBDII code P119F NOx Sensor 2 Signal Circuit High Voltage in a 2018 GMC Sierra?

Regularly scheduled maintenance, such as inspecting and replacing sensors as recommended by the manufacturer, keeping the engine well-tuned, and using high-quality fuel, can help prevent issues like this code from occurring.

10. How long does it typically take to repair OBDII code P119F NOx Sensor 2 Signal Circuit High Voltage in a 2018 GMC Sierra?

The repair time can vary depending on the exact cause of the issue and the availability of parts, but it may take anywhere from a few hours to a full day to diagnose and fix the problem.