AutoCodes – Chevrolet – P11FE Chevrolet

P11FE Chevrolet Code - O2 Low Reference Circuit High Voltage (NOx Sensor 2)

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: P11FE Chevrolet indicates O2 Low Reference Circuit High Voltage (NOx Sensor 2).
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 426

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 P11FE Chevrolet 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 P11FE Chevrolet - O2 Low Reference Circuit High Voltage (NOx Sensor 2) - AutoCodes.com — P11FE Chevrolet Code - O2 Low Reference Circuit High Voltage (NOx Sensor 2)

What does this mean?

What are the Possible Causes of the DTC P11FE Chevrolet?

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 P11FE Chevrolet?

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 P11FE Chevrolet 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 P11FE Chevrolet code?

Need more information on how to fix the P11FE Chevrolet code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P11FE Chevrolet code diagnosed by a professional: Find a repair shop in your area

Information for Specific Chevrolet Models

P11FE 2014 Chevrolet Silverado — O2 Low Reference Circuit High Voltage (NOx Sensor 2)
P11FE 2015 Chevrolet Silverado — O2 Low Reference Circuit High Voltage (NOx Sensor 2)
P11FE 2016 Chevrolet Silverado — O2 Low Reference Circuit High Voltage (NOx Sensor 2)
P11FE 2017 Chevrolet Silverado — O2 Low Reference Circuit High Voltage (NOx Sensor 2)
P11FE 2018 Chevrolet Silverado — O2 Low Reference Circuit High Voltage (NOx Sensor 2)

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 P11FE Chevrolet Code

1. What are the common symptoms of OBDII code P11FE in a Chevrolet related to the NOx Sensor 2?

- Common symptoms include poor engine performance, reduced fuel efficiency, and the illumination of the Check Engine Light.

2. What can cause the O2 Low Reference Circuit High Voltage (NOx Sensor 2) error code P11FE in a Chevrolet?

- Possible causes can include a faulty NOx sensor, damaged wiring or connectors, a malfunctioning powertrain control module (PCM), or exhaust system issues.

3. How can I diagnose the OBDII code P11FE related to the NOx Sensor 2 in my Chevrolet?

- Diagnosis involves using an OBDII scanner to retrieve the specific fault code, inspecting the NOx sensor and its wiring for damage, and testing the sensor's functionality.

4. Is it safe to continue driving my Chevrolet with the P11FE error code indicating an issue with the NOx Sensor 2?

- It is not recommended to drive the vehicle with an unresolved P11FE code, as it can lead to further damage and potentially affect emissions compliance.

5. Can I reset the Check Engine Light after repairing the O2 Low Reference Circuit High Voltage fault code in my Chevrolet?

- Yes, once the underlying issue causing the P11FE code is fixed, the Check Engine Light can be reset using an OBDII scanner to clear the code.

6. How much does it typically cost to repair the OBDII code P11FE in a Chevrolet related to the NOx Sensor 2?

- Repair costs can vary depending on the exact cause of the issue, but it may involve replacing the NOx sensor, repairing wiring, or addressing other related components. Costs can range from $200 to $600 or more.

7. Are there any DIY repair tips for addressing the O2 Low Reference Circuit High Voltage fault code (P11FE) in a Chevrolet?

- DIY enthusiasts with automotive knowledge may attempt to inspect wiring and connectors for damage, clean connections, or replace the NOx sensor themselves. However, professional diagnosis and repair are recommended for accurate resolution.

8. Can a faulty NOx Sensor 2 cause other issues in my Chevrolet besides triggering the P11FE fault code?

- Yes, a malfunctioning NOx sensor can impact overall engine performance, emissions output, and fuel efficiency in addition to triggering the Check Engine Light with the P11FE error code.

9. How often should the NOx sensors in a Chevrolet be inspected or replaced to prevent OBDII code P11FE from occurring?

- It is recommended to follow the manufacturer's maintenance schedule for sensor inspection and replacement to prevent issues like the P11FE code. Typically, sensors may need replacement every 50,000 to 100,000 miles.

10. Will fixing the O2 Low Reference Circuit High Voltage fault code (P11FE) improve my Chevrolet's fuel economy and performance?

- Yes, addressing the underlying issue causing the P11FE code, such as a faulty NOx sensor, can lead to improved fuel economy, engine performance, and emissions compliance in your Chevrolet.