AutoCodes – GMC – P116C GMC

P116C GMC Code - O2 Signal Circuit High Voltage (NOx Sensor 1)

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: P116C GMC indicates O2 Signal Circuit High Voltage (NOx Sensor 1).
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 444

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 29, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P116C GMC 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 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 P116C GMC - O2 Signal Circuit High Voltage (NOx Sensor 1) - AutoCodes.com — P116C GMC Code - O2 Signal Circuit High Voltage (NOx Sensor 1)

What does this mean?

What are the Possible Causes of the DTC P116C GMC?

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 P116C GMC?

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 P116C GMC 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 P116C GMC code?

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Information for Specific GMC Models

P116C 2014 GMC Sierra — O2 Signal Circuit High Voltage (NOx Sensor 1)
P116C 2015 GMC Sierra — O2 Signal Circuit High Voltage (NOx Sensor 1)
P116C 2016 GMC Sierra — O2 Signal Circuit High Voltage (NOx Sensor 1)
P116C 2017 GMC Sierra — O2 Signal Circuit High Voltage (NOx Sensor 1)
P116C 2018 GMC Sierra — O2 Signal Circuit High Voltage (NOx Sensor 1)

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 P116C GMC Code

1. What are the common symptoms of OBDII code P116C GMC?

- Common symptoms include poor engine performance, reduced fuel efficiency, and the illumination of the check engine light.

2. What are the possible causes of O2 Signal Circuit High Voltage (NOx Sensor 1) code P116C in a GMC vehicle?

- Possible causes include a faulty NOx sensor, wiring issues in the O2 signal circuit, or problems with the powertrain control module (PCM).

3. How can I diagnose the O2 signal circuit high voltage issue related to code P116C in my GMC vehicle?

- Diagnose by checking the NOx sensor wiring for damage, testing the sensor's resistance and voltage output, and inspecting the PCM for any faults.

4. Can a dirty or contaminated NOx sensor trigger OBDII code P116C in a GMC vehicle?

- Yes, a dirty or contaminated NOx sensor can cause erroneous readings and trigger code P116C due to high voltage in the O2 signal circuit.

5. What are some repair tips for addressing code P116C GMC related to the O2 signal circuit high voltage issue?

- Repair tips include cleaning or replacing the NOx sensor, repairing any damaged wiring, and resetting the fault codes after completing the repairs.

6. Is it safe to continue driving my GMC vehicle with OBDII code P116C indicating a high voltage issue in the O2 signal circuit?

- It is not recommended to drive the vehicle with code P116C present, as it can lead to further damage and potentially affect the vehicle's emissions performance.

7. Can a DIY enthusiast fix O2 signal circuit high voltage issues related to code P116C in a GMC vehicle?

- While some basic troubleshooting and repairs can be done by a DIY enthusiast, complex diagnostics and sensor replacements may require professional assistance.

8. How important is it to address code P116C GMC promptly to avoid potential engine damage?

- It is important to address code P116C promptly to prevent potential engine damage, ensure optimal fuel efficiency, and maintain the vehicle's emissions compliance.

9. Are there any recalls or technical service bulletins related to OBDII code P116C in GMC vehicles?

- It is recommended to check with the manufacturer or a GMC dealership for any recalls or technical service bulletins related to code P116C and the NOx sensor issue.

10. What is the typical cost of repairing O2 signal circuit high voltage issues associated with code P116C in a GMC vehicle?

- The cost of repair can vary depending on the exact cause of the issue, but it may involve sensor replacement, wiring repairs, or PCM reprogramming, potentially ranging from $200 to $800 or more.