AutoCodes – Buick – P11C7 Buick

P11C7 Buick Code - NOx Sensor 2 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 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: P11C7 Buick indicates NOx Sensor 2 Heater Ground Circuit.
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 411

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 P11C7 Buick 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 P11C7 Buick - NOx Sensor 2 Heater Ground Circuit - AutoCodes.com — P11C7 Buick Code - NOx Sensor 2 Heater Ground Circuit

What does this mean?

What are the Possible Causes of the DTC P11C7 Buick?

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 P11C7 Buick?

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 P11C7 Buick 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 P11C7 Buick Code

1. What are common symptoms of an OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit in a Buick?

Common symptoms include decreased fuel efficiency, engine misfires, rough idling, and the illumination of the Check Engine Light.

2. What causes the OBDII code P11C7 in a Buick related to the NOx Sensor 2 Heater Ground Circuit?

The code P11C7 is typically triggered by issues with the NOx Sensor 2 heater ground circuit, such as wiring faults, a faulty NOx sensor, or a malfunctioning heater element.

3. How can I diagnose the OBDII code P11C7 in my Buick related to the NOx Sensor 2 Heater Ground Circuit?

Diagnosing the code usually involves using an OBDII scanner to retrieve the specific fault code, inspecting the wiring and connections related to the NOx sensor, and testing the sensor's functionality.

4. Can I drive my Buick with an active OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit?

It's generally not recommended to drive your vehicle with an active P11C7 code, as it can lead to decreased performance and potential damage to the engine or emissions system.

5. How can I repair the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit in my Buick?

Repairing the issue may involve repairing or replacing damaged wiring, replacing the NOx sensor, or addressing any faults with the heater element to ensure proper functionality.

6. Is it possible to reset the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit without fixing the underlying issue?

While you can clear the code with an OBDII scanner, it's important to address the root cause of the problem to prevent the code from reoccurring and ensure proper vehicle operation.

7. How much does it cost to repair the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit in a Buick?

The cost of repair can vary depending on the specific issue, but it may involve labor costs for diagnosis and repair, as well as the cost of any replacement parts needed.

8. Can a DIY enthusiast fix the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit in a Buick?

DIY enthusiasts with the necessary tools and experience may be able to address simpler issues like damaged wiring, but more complex problems may require professional diagnosis and repair.

9. Will the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit cause my Buick to fail an emissions test?

Having an active P11C7 code can indicate issues with the emissions system, potentially leading to a failed emissions test. It's recommended to address the problem before undergoing testing.

10. Are there any preventative measures to avoid the OBDII code P11C7 related to the NOx Sensor 2 Heater Ground Circuit in a Buick?

Regular maintenance, such as ensuring timely sensor replacements and addressing any wiring issues promptly, can help prevent the occurrence of the P11C7 code in your Buick.