AutoCodes – Chevrolet – P11BF 2014 Chevrolet Silverado

P11BF 2014 Chevrolet Silverado Code - O2 Reference Voltage Circuit Low 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: P11BF 2014 Chevrolet Silverado indicates O2 Reference Voltage Circuit Low 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 246

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
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P11BF 2014 Chevrolet Silverado 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 P11BF 2014 Chevrolet Silverado - O2 Reference Voltage Circuit Low Voltage (NOx Sensor 2) - AutoCodes.com — P11BF 2014 Chevrolet Silverado Code - O2 Reference Voltage Circuit Low Voltage (NOx Sensor 2)

What does this mean?

What are the Possible Causes of the DTC P11BF 2014 Chevrolet Silverado?

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 P11BF 2014 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 P11BF 2014 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 P11BF 2014 Chevrolet Silverado code?

Need more information on how to fix the P11BF 2014 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P11BF 2014 Chevrolet Silverado code diagnosed by a professional: Find a repair shop in your area

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 P11BF 2014 Chevrolet Silverado Code

What does OBDII code P11BF mean?

Code P11BF indicates that the O2 reference voltage circuit for NOx Sensor 2 is reporting a low voltage condition, suggesting an issue with the sensor or its circuit.

What are the symptoms of code P11BF in a 2014 Chevrolet Silverado?

Symptoms may include the check engine light turning on, reduced fuel efficiency, poor engine performance, or difficulty passing emissions tests.

What causes code P11BF in a 2014 Chevrolet Silverado?

Common causes include a faulty NOx Sensor 2, damaged wiring or connectors in the reference voltage circuit, or issues with the vehicle's engine control module (ECM).

Can a bad NOx sensor cause code P11BF?

Yes, a malfunctioning NOx Sensor 2 can cause this code by failing to provide the correct reference voltage signal.

How can I diagnose code P11BF in a 2014 Chevrolet Silverado?

Start by visually inspecting the wiring and connectors for damage or corrosion, then test the NOx sensor for proper operation using a multimeter or diagnostic tool.

Can code P11BF affect fuel efficiency?

Yes, a malfunctioning NOx sensor can lead to improper air-fuel mixture adjustments, reducing fuel efficiency.

How do I fix code P11BF in my 2014 Chevrolet Silverado?

Repairs may involve replacing the NOx Sensor 2, repairing damaged wiring or connectors, or, in rare cases, updating or replacing the ECM.

Is it safe to drive with code P11BF?

While the vehicle may still be drivable, ignoring this code can lead to reduced performance, higher emissions, and potential damage to other engine components.

How much does it cost to repair code P11BF?

Repair costs can vary but typically range from $200 to $800 depending on whether the NOx sensor or wiring needs replacement.

Can a software update fix code P11BF in a 2014 Chevrolet Silverado?

In some cases, a software update for the ECM may resolve the issue, but this depends on the specific circumstances and should be determined by a professional mechanic.