U029E 2016 GMC Sierra Code - Lost Communication with NOX Sensor Module 2 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 2, Nitrogen Oxide Sensor Module 2 harness is open or shorted, Nitrogen Oxide Sensor Module 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
- U029E 2016 GMC Sierra indicates Lost Communication with NOX Sensor Module 2 Malfunction.
- Common causes
- Common causes include Faulty Nitrogen Oxide (NOx) Sensor Module 2, Nitrogen Oxide Sensor Module 2 harness is open or shorted, Nitrogen Oxide Sensor Module 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.
Code U029E 2016 GMC Sierra Description
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.
What are the Possible Causes of the DTC U029E 2016 GMC Sierra?
- Faulty Nitrogen Oxide (NOx) Sensor Module 2
- Nitrogen Oxide Sensor Module 2 harness is open or shorted
- Nitrogen Oxide Sensor Module 2 circuit poor electrical connection
How to Fix the DTC U029E 2016 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 U029E 2016 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.
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Frequently Asked Questions about U029E 2016 GMC Sierra Code
What does the OBDII code U029E mean on a 2016 GMC Sierra?
It means there is a loss of communication between the vehicle's computer and the NOx Sensor Module 2, which monitors nitrogen oxide emissions.
What are the common symptoms of the U029E code?
Symptoms may include an illuminated check engine light, reduced engine performance, increased emissions, or issues with fuel efficiency.
What causes the U029E code to appear?
Common causes include a faulty NOx sensor, damaged wiring or connectors, a failed NOx sensor module, or communication issues in the CAN bus network.
Can I drive my GMC Sierra with the U029E code?
Driving is possible but not recommended, as it can lead to increased emissions, potential engine damage, and failure to meet emissions standards.
How can I diagnose the U029E code?
Start by checking the wiring and connectors for damage or corrosion, inspecting the NOx sensor, and using a scan tool to verify communication with the NOx Sensor Module 2.
Is the problem likely to be with the sensor or the vehicle's computer?
While the sensor is often the culprit, the issue can also stem from wiring, connectors, or the vehicle's CAN bus system.
How do I fix the U029E code on a 2016 GMC Sierra?
Repairs may include replacing the faulty NOx sensor, repairing damaged wiring or connectors, or addressing issues in the CAN bus network.
What tools are needed to troubleshoot the U029E code?
You’ll need an OBDII scan tool with CAN bus communication capabilities, a multimeter for testing wiring, and possibly a diagnostic flowchart for your vehicle.
How much does it cost to repair a U029E code?
Costs vary but typically range from $200 to $600, depending on whether you need to replace the NOx sensor or repair wiring and connectors.
Will clearing the code fix the problem?
Clearing the code will only reset the warning temporarily. The underlying issue must be repaired to prevent the code from returning.
Discuss the causes and fixes for U029E 2016 GMC Sierra OBDII Code
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