AutoCodes – Chevrolet – P1194 2015 Chevrolet Silverado

P1194 2015 Chevrolet Silverado Code - O2 Low Reference 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: P1194 2015 Chevrolet Silverado indicates O2 Low Reference 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 307

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 P1194 2015 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 P1194 2015 Chevrolet Silverado - O2 Low Reference Circuit High Voltage (NOx Sensor 1) - AutoCodes.com — P1194 2015 Chevrolet Silverado Code - O2 Low Reference Circuit High Voltage (NOx Sensor 1)

What does this mean?

What are the Possible Causes of the DTC P1194 2015 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 P1194 2015 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 P1194 2015 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 P1194 2015 Chevrolet Silverado code?

Need more information on how to fix the P1194 2015 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1194 2015 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 P1194 2015 Chevrolet Silverado Code

1. What does OBDII code P1194 on a 2015 Chevrolet Silverado mean?

- OBDII code P1194 indicates a problem with the O2 Low Reference Circuit High Voltage for NOx Sensor 1 in your 2015 Chevrolet Silverado.

2. What are the common symptoms of OBDII code P1194 in a 2015 Chevrolet Silverado?

- Common symptoms of code P1194 may include poor engine performance, decreased fuel efficiency, rough idling, and illuminated Check Engine Light.

3. What are the possible causes of OBDII code P1194 in a 2015 Chevrolet Silverado?

- Causes of code P1194 can include a faulty NOx sensor, damaged wiring or connectors in the O2 sensor circuit, an issue with the engine control module (ECM), or a vacuum leak in the system.

4. How can I diagnose OBDII code P1194 in a 2015 Chevrolet Silverado?

- Diagnosing code P1194 may involve using an OBDII scanner to retrieve the trouble code, inspecting the NOx sensor and its wiring for damage, and testing the sensor's voltage output.

5. Can I drive my 2015 Chevrolet Silverado with OBDII code P1194?

- It is not recommended to drive your vehicle with an unresolved P1194 code, as it can lead to further damage and potentially worsen the vehicle's performance.

6. How do I repair OBDII code P1194 in a 2015 Chevrolet Silverado?

- Repairing code P1194 may involve replacing the NOx sensor, repairing or replacing damaged wiring or connectors, resetting the ECM, and clearing the trouble code.

7. Are there any DIY tips for fixing OBDII code P1194 in a 2015 Chevrolet Silverado?

- DIY tips for addressing code P1194 include checking for loose connections, ensuring proper sensor installation, and following the manufacturer's repair procedures.

8. What happens if I ignore OBDII code P1194 in my 2015 Chevrolet Silverado?

- Ignoring code P1194 can lead to reduced fuel efficiency, potential engine damage, and may cause your vehicle to fail emissions tests.

9. Is it safe to reset the Check Engine Light after repairing OBDII code P1194 in a 2015 Chevrolet Silverado?

- Yes, it is safe to reset the Check Engine Light after repairing code P1194, but make sure the issue is resolved to prevent the light from coming back on.

10. How can I prevent OBDII code P1194 from occurring again in my 2015 Chevrolet Silverado?

- To prevent code P1194, ensure regular maintenance of your vehicle, address any issues promptly, and use quality parts when replacing sensors or components.