AutoCodes – GMC – P1111 2014 GMC Sierra

P1111 2014 GMC Sierra Code - Intake Air Temperature Sensor Circuit Intermittent High Voltage

Quick Answer

The Intake Air Temperature (IAT) sensor 1 is a variable resistor that changes the voltage on the Engine Control Module (ECM) supplied 5 V signal circuit. Common causes include Faulty Intake Air Temperature (IAT) sensor (Integrated within the Mass Air Flow / Multifunction Intake Air Sensor), Intake Air Temperature sensor harness is open or shorted, Intake Air Temperature 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: P1111 2014 GMC Sierra indicates Intake Air Temperature Sensor Circuit Intermittent High Voltage.
Common causes: Common causes include Faulty Intake Air Temperature (IAT) sensor (Integrated within the Mass Air Flow / Multifunction Intake Air Sensor), Intake Air Temperature sensor harness is open or shorted, Intake Air Temperature 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.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

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

Code Popularity 326

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 30, 2022

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
Comments
Add Comment

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

Code P1111 2014 GMC Sierra Description

The Intake Air Temperature (IAT) sensor 1 is a variable resistor that changes the voltage on the Engine Control Module (ECM) supplied 5 V signal circuit. The signal varies with inlet air temperature in the sensor bore and is displayed by the scan tool as °C (°F). The IAT sensor 2 and the humidity sensor share the same circuit. The IAT sensor 2 signal is displayed by the scan tool as Hertz (Hz) and °C (°F). The Diagnostic Trouble Code (DTC) will be set when the ECM detects a fault is detected on the IAT signal or control circuits.

OBDII Code P1111 2014 GMC Sierra - Intake Air Temperature Sensor Circuit Intermittent High Voltage - AutoCodes.com — P1111 2014 GMC Sierra Code - Intake Air Temperature Sensor Circuit Intermittent High Voltage

What does this mean?

What are the Possible Causes of the DTC P1111 2014 GMC Sierra?

Faulty Intake Air Temperature (IAT) sensor (Integrated within the Mass Air Flow / Multifunction Intake Air Sensor)
Intake Air Temperature sensor harness is open or shorted
Intake Air Temperature sensor circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P1111 2014 GMC Sierra?

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 does this mean?

Code Tech Notes

The Intake Air Temperature (IAT) sensor 1, IAT sensor 2, Humidity sensor, MAF sensor, and BARO pressure sensor are integrated within the Mass Air Flow / Multifunction Intake Air Sensor.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1111 2014 GMC Sierra 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 P1111 2014 GMC Sierra code?

Need more information on how to fix the P1111 2014 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1111 2014 GMC Sierra 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.