AutoCodes – Chevrolet – P11C5 2018 Chevrolet Silverado

P11C5 2018 Chevrolet Silverado Code - NOx Sensor 1 Heater Ground Circuit

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, Nitrogen Oxides Sensor harness is open or shorted, Nitrogen Oxides Sensor 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: P11C5 2018 Chevrolet Silverado indicates NOx Sensor 1 Heater Ground Circuit.
Common causes: Common causes include Faulty Nitrogen Oxides (NOx) Sensor, Nitrogen Oxides Sensor harness is open or shorted, Nitrogen Oxides Sensor 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 343

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 Mar 24, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P11C5 2018 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 P11C5 2018 Chevrolet Silverado - NOx Sensor 1 Heater Ground Circuit - AutoCodes.com — P11C5 2018 Chevrolet Silverado Code - NOx Sensor 1 Heater Ground Circuit

What does this mean?

What are the Possible Causes of the DTC P11C5 2018 Chevrolet Silverado?

Faulty Nitrogen Oxides (NOx) Sensor
Nitrogen Oxides Sensor harness is open or shorted
Nitrogen Oxides Sensor circuit poor electrical connection

How to Fix the DTC P11C5 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 P11C5 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 P11C5 2018 Chevrolet Silverado code?

Need more information on how to fix the P11C5 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P11C5 2018 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 P11C5 2018 Chevrolet Silverado Code

1. What does the OBDII code P11C5 mean on a 2018 Chevrolet Silverado?

The P11C5 code indicates an issue with the NOx Sensor 1 Heater Ground Circuit, which can affect the proper functioning of the NOx sensor.

2. What are the common symptoms of the P11C5 code?

Symptoms may include a check engine light, reduced fuel efficiency, poor engine performance, or the truck entering limp mode.

3. What causes the P11C5 code to appear?

Common causes include a damaged NOx sensor, faulty wiring or connectors in the heater ground circuit, or a malfunctioning engine control module (ECM).

4. Can I drive with the P11C5 code active?

It is not recommended to drive for extended periods with this code, as it may lead to higher emissions, reduced performance, and potential damage to other components.

5. How do I diagnose the P11C5 code?

Diagnosis typically involves inspecting the NOx sensor, checking the wiring and connectors for damage or corrosion, and testing the heater ground circuit with a multimeter.

6. How is the P11C5 code fixed?

Repairs may include replacing the NOx sensor, repairing or replacing damaged wiring or connectors, or reprogramming/updating the ECM if necessary.

7. How much does it cost to repair the P11C5 code?

The cost can vary, but replacing a NOx sensor typically ranges from $300 to $700, depending on parts and labor.

8. Can a software update fix the P11C5 code?

In some cases, a software update or ECM reprogramming may resolve the issue if the problem is related to incorrect sensor communication.

9. What happens if I ignore the P11C5 code?

Ignoring the code can lead to increased emissions, potential damage to the catalytic converter, and reduced engine efficiency over time.

10. Is the NOx sensor covered under warranty for a 2018 Chevrolet Silverado?

The NOx sensor may be covered under the emissions warranty, depending on the vehicle's age, mileage, and specific warranty terms. Check with your dealership for details.