AutoCodes – Generic – P119D

P119D Code - NOx Sensor 2 Signal Circuit

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: P119D indicates NOx Sensor 2 Signal Circuit.
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 2,861

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 P119D 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 P119D - NOx Sensor 2 Signal Circuit - AutoCodes.com — P119D Code - NOx Sensor 2 Signal Circuit

What does this mean?

What are the Possible Causes of the DTC P119D?

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 P119D?

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 P119D 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 P119D code?

Need more information on how to fix the P119D code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P119D code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P119D Buick — NOx Sensor 2 Signal Circuit
P119D Cadillac — NOx Sensor 2 Signal Circuit
P119D Chevrolet — NOx Sensor 2 Signal Circuit
P119D GMC — NOx Sensor 2 Signal Circuit

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 P119D Code

1. What are the common symptoms of OBDII code P119D (NOx Sensor 2 Signal Circuit)?

The common symptoms of code P119D include poor engine performance, decreased fuel efficiency, and the illumination of the check engine light.

2. What are the possible causes of OBDII code P119D?

Possible causes of code P119D include a faulty NOx sensor, damaged wiring or connectors in the sensor circuit, or issues with the engine control module (ECM).

3. How can I diagnose the cause of OBDII code P119D?

Diagnosing code P119D involves using a scan tool to read the code and checking the NOx sensor, wiring, and connectors for any visible damage or issues. It may also require testing the sensor's signal output.

4. Can I continue driving with OBDII code P119D present?

It is not recommended to continue driving with code P119D present, as it can lead to further damage to the vehicle and may result in increased emissions.

5. How can I repair OBDII code P119D?

Repairing code P119D involves replacing the faulty NOx sensor, repairing any damaged wiring or connectors in the sensor circuit, or addressing any ECM issues that may be causing the code.

6. Is it possible to reset OBDII code P119D without fixing the underlying issue?

While clearing the code may temporarily turn off the check engine light, the underlying issue causing code P119D will still persist and may trigger the code again in the future.

7. Can a DIY enthusiast fix OBDII code P119D at home?

Depending on their skill level and access to tools, a DIY enthusiast may be able to fix code P119D by replacing the NOx sensor or repairing the wiring themselves. However, some cases may require professional assistance.

8. Are there any preventive measures to avoid OBDII code P119D?

Regular vehicle maintenance, such as checking and replacing sensors as recommended by the manufacturer, can help prevent issues that may trigger code P119D.

9. How long does it typically take to repair OBDII code P119D?

The repair time for code P119D can vary depending on the exact cause of the issue and the extent of the repairs needed, but it can typically be resolved within a few hours to a day.

10. Will fixing OBDII code P119D improve my vehicle's performance and fuel efficiency?

Yes, addressing and fixing code P119D can help improve your vehicle's performance and fuel efficiency by ensuring that the NOx sensor is functioning properly and accurately monitoring emissions.