AutoCodes – Chevrolet – U029D 2018 Chevrolet Silverado

U029D 2018 Chevrolet Silverado Code - Lost Communication with NOX Sensor Module 1 Malfunction

Quick Answer

The reductant system uses two Nitrogen Oxide (NOx) sensors to monitor the amount of NOx in the engine's exhaust gas. Common causes include Faulty Nitrogen Oxide (NOx) Sensor Module 1, Nitrogen Oxide Sensor Module 1 harness is open or shorted, Nitrogen Oxide Sensor Module 1 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: U029D 2018 Chevrolet Silverado indicates Lost Communication with NOX Sensor Module 1 Malfunction.
Common causes: Common causes include Faulty Nitrogen Oxide (NOx) Sensor Module 1, Nitrogen Oxide Sensor Module 1 harness is open or shorted, Nitrogen Oxide Sensor Module 1 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 387

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 Oct 18, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U029D 2018 Chevrolet Silverado Description

The reductant system uses two Nitrogen Oxide (NOx) sensors to monitor the amount of NOx in the engine's exhaust gas. The first sensor is located at the outlet of the turbocharger and monitors the engine out NOx level. The second NOx sensor is located between the Selective Catalytic Reduction (SCR) and the Diesel Particulate Filter (DPF) and monitors NOx levels downstream of the SCR. The second NOx sensor also provides the Engine Control Module (ECM) with information on the exhaust oxygen level during DPF regeneration.
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 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 (DEF) or reductant added by varying the reductant injector duty cycle in response to changes in engine exhaust out 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.

OBDII Code U029D 2018 Chevrolet Silverado - Lost Communication with NOX Sensor Module 1 Malfunction - AutoCodes.com — U029D 2018 Chevrolet Silverado Code - Lost Communication with NOX Sensor Module 1 Malfunction

What does this mean?

What are the Possible Causes of the DTC U029D 2018 Chevrolet Silverado?

Faulty Nitrogen Oxide (NOx) Sensor Module 1
Nitrogen Oxide Sensor Module 1 harness is open or shorted
Nitrogen Oxide Sensor Module 1 circuit poor electrical connection

How to Fix the DTC U029D 2018 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 U029D 2018 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 U029D 2018 Chevrolet Silverado code?

Need more information on how to fix the U029D 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals

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 U029D 2018 Chevrolet Silverado Code

1. What does the OBDII code U029D on a 2018 Chevrolet Silverado mean?

The code U029D indicates a "Lost Communication with NOX Sensor Module 1 Malfunction" in a 2018 Chevrolet Silverado.

2. What are common symptoms of the U029D code in a 2018 Chevrolet Silverado?

Common symptoms of the U029D code may include the check engine light being illuminated, reduced engine performance, and potential issues with emissions control.

3. What can cause the U029D code to appear in a 2018 Chevrolet Silverado?

The U029D code can be triggered by issues such as a faulty NOX sensor, damaged wiring or connectors, software glitches, or a malfunction in the NOX sensor module.

4. How can I diagnose the U029D code on a 2018 Chevrolet Silverado?

To diagnose the U029D code, a thorough inspection of the NOX sensor, wiring, and connectors is recommended, along with potentially using a scan tool to communicate with the NOX sensor module.

5. Can I continue driving my 2018 Chevrolet Silverado with the U029D code?

While it may be possible to continue driving with the U029D code present, it is advisable to address the issue promptly to prevent potential damage to the vehicle and ensure optimal performance.

6. How can I repair the U029D code on a 2018 Chevrolet Silverado?

Repairing the U029D code may involve replacing the NOX sensor, repairing damaged wiring or connectors, updating software, or addressing any malfunctions in the NOX sensor module.

7. Are there any DIY tips for fixing the U029D code on a 2018 Chevrolet Silverado?

DIY tips for addressing the U029D code include checking for loose or damaged connections, inspecting the NOX sensor for signs of damage, and consulting the vehicle's service manual for specific repair procedures.

8. Is the U029D code a serious issue in a 2018 Chevrolet Silverado?

While the U029D code may not cause immediate drivability issues, it is essential to address it promptly to ensure proper emissions control and prevent potential long-term damage to the vehicle.

9. Can resetting the trouble codes clear the U029D code on a 2018 Chevrolet Silverado?

Resetting the trouble codes may temporarily clear the U029D code, but if the underlying issue is not addressed, the code is likely to reappear. It is recommended to diagnose and repair the root cause of the problem.

10. How much does it typically cost to repair the U029D code on a 2018 Chevrolet Silverado?

The cost of repairing the U029D code can vary depending on the specific issue causing the malfunction. Costs may include parts, labor, diagnostic fees, and any necessary software updates. It is advisable to consult a professional mechanic for an accurate estimate.