AutoCodes – RAM – U029E RAM

U029E RAM Code - Lost Communication With NOX Sensor 'B'

Quick Answer

The aftertreatment system is equipped with two NOx Sensors and modules. Common causes include Low Battery Voltage, Faulty Nitrogen Oxide (NOx) Sensor Bank 'B', Nitrogen Oxide (NOx) Sensor Bank 'B' harness is open or shorted. 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: U029E RAM indicates Lost Communication With NOX Sensor 'B'.
Common causes: Common causes include Low Battery Voltage, Faulty Nitrogen Oxide (NOx) Sensor Bank 'B', Nitrogen Oxide (NOx) Sensor Bank 'B' harness is open or shorted.
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 3,104

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 Apr 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U029E RAM Description

The aftertreatment system is equipped with two NOx Sensors and modules. The upstream NOx Sensor 1/1 is located on the Turbocharger elbow downpipe and is permanently connected to a corresponding NOx Sensor Module mounted to the hot side of the engine block. The downstream NOx Sensor 1/2 is located at the outlet of the SCR Catalyst and is permanently connected to a corresponding NOx Sensor Module which is mounted on the right frame rail. The NOx Sensors and NOx Sensor Modules are calibrated to each other and must be replaced as an assembly. The two NOx Sensor and Module assemblies are not interchangeable. The NOx Sensor Modules are smart devices and communicate with the Powertrain Control Module (PCM) over the J1939 Data Link. The NOx Sensor Modules perform their own internal diagnostics and report malfunctions back to the PCM. The NOx Sensors are used to monitor the efficiency of the SCR Catalyst and dosing system. The PCM will illuminate the Malfunction Indicator Lamp (MIL) after the diagnostic runs and fails in two consecutive drive cycles. The PCM will turn off the MIL immediately after the monitor runs and passes.

OBDII Code U029E RAM - Lost Communication With NOX Sensor 'B' - AutoCodes.com — U029E RAM Code - Lost Communication With NOX Sensor 'B'

What does this mean?

What are the Possible Causes of the DTC U029E RAM?

Low Battery Voltage
Faulty Nitrogen Oxide (NOx) Sensor Bank 'B'
Nitrogen Oxide (NOx) Sensor Bank 'B' harness is open or shorted
Nitrogen Oxide (NOx) Sensor Bank 'B' circuit poor electrical connection
Faulty Powertrain Control Module (PCM)

How to Fix the DTC U029E RAM?

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 U029E RAM 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.

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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 U029E RAM Code

1. What are the common symptoms of OBDII code U029E RAM Lost Communication With NOX Sensor 'B'?

- Common symptoms include the check engine light coming on, poor engine performance, and possible issues with emissions.

2. What could be causing the U029E code related to lost communication with the NOX Sensor 'B'?

- Possible causes include a faulty NOX sensor, damaged wiring or connectors, a blown fuse, or issues with the engine control module.

3. How can I diagnose the U029E code for lost communication with the NOX Sensor 'B'?

- Diagnosing the issue involves using a scan tool to check for the code, inspecting the NOX sensor and related wiring, and testing the power and ground connections.

4. What should I check first when troubleshooting the U029E code for communication loss with the NOX Sensor 'B'?

- Start by checking the NOX sensor connections, ensuring they are secure and free of corrosion or damage that could be causing a loss of communication.

5. Can I drive my vehicle with the U029E code related to the NOX Sensor 'B' communication issue?

- It is not recommended to drive with this code present, as it can lead to poor engine performance and potential emission system problems.

6. How do I repair the U029E code for lost communication with the NOX Sensor 'B'?

- Repair options may include replacing the NOX sensor, repairing damaged wiring or connectors, checking and replacing fuses, or reprogramming the engine control module.

7. Is it possible to clear the U029E code for NOX Sensor 'B' communication loss without fixing the issue?

- Clearing the code without fixing the underlying problem is not recommended, as it could lead to ongoing issues with engine performance and emissions.

8. Can a DIY enthusiast fix the U029E code related to lost communication with the NOX Sensor 'B'?

- Depending on the cause of the issue, some DIY enthusiasts may be able to address the problem by replacing the NOX sensor or repairing wiring connections.

9. How much does it typically cost to repair the U029E code for lost communication with the NOX Sensor 'B'?

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

10. Are there any preventative measures to avoid encountering the U029E code for NOX Sensor 'B' communication loss in the future?

- Regular vehicle maintenance, such as checking and cleaning sensor connections, inspecting wiring for damage, and addressing any engine performance issues promptly, can help prevent this code from occurring.