AutoCodes – GMC – P2122 2018 GMC Sierra

P2122 2018 GMC Sierra Code - Accelerator Pedal Position Sensor 1 Circuit Low Voltage

Quick Answer

The Accelerator Pedal Assembly contains 2 Accelerator Pedal Position (APP) sensors. Common causes include Faulty Accelerator Pedal Position Sensor, Accelerator Pedal Position Sensor harness is open or shorted, Accelerator Pedal Position 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: P2122 2018 GMC Sierra indicates Accelerator Pedal Position Sensor 1 Circuit Low Voltage.
Common causes: Common causes include Faulty Accelerator Pedal Position Sensor, Accelerator Pedal Position Sensor harness is open or shorted, Accelerator Pedal Position 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 292

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 08, 2022

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code P2122 2018 GMC Sierra Description

The Accelerator Pedal Assembly contains 2 Accelerator Pedal Position (APP) sensors. The APP sensors are mounted to the accelerator pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the pedal position. The Engine Control Module (ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.
Both the APP sensors 1 and 2 signal percentages increase as the pedal is depressed, from approximately 0 percent at rest to above 95 percent when fully depressed.
The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the APP sensor 1 voltage is less than 0.46 V for less than 1 s.

OBDII Code P2122 2018 GMC Sierra - Accelerator Pedal Position Sensor 1 Circuit Low Voltage - AutoCodes.com — P2122 2018 GMC Sierra Code - Accelerator Pedal Position Sensor 1 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P2122 2018 GMC Sierra?

Faulty Accelerator Pedal Position Sensor
Accelerator Pedal Position Sensor harness is open or shorted
Accelerator Pedal Position Sensor circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P2122 2018 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

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2122 2018 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.

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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 P2122 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P2122 in a 2018 GMC Sierra?

- Common symptoms include poor acceleration, reduced engine power, and the illumination of the Check Engine light.

2. What does the OBDII code P2122 for Accelerator Pedal Position Sensor 1 Circuit Low Voltage indicate in a 2018 GMC Sierra?

- This code indicates that there is a low voltage condition detected in the circuit of the accelerator pedal position sensor.

3. What are the potential causes of OBDII code P2122 in a 2018 GMC Sierra?

- Potential causes include a faulty accelerator pedal position sensor, damaged wiring or connectors in the sensor circuit, or issues with the vehicle's electronic control module.

4. How can I diagnose the cause of OBDII code P2122 in my 2018 GMC Sierra?

- Diagnosing the issue involves checking the accelerator pedal position sensor for proper operation, inspecting the sensor wiring and connectors for damage, and scanning the vehicle's computer for related trouble codes.

5. Can I still drive my 2018 GMC Sierra with OBDII code P2122?

- It is not recommended to drive with this code present, as it can lead to reduced performance and potential safety issues. It is best to address the problem promptly.

6. How can I repair OBDII code P2122 in my 2018 GMC Sierra?

- Repair involves replacing the faulty accelerator pedal position sensor, repairing any damaged wiring or connectors, and clearing the trouble codes from the vehicle's computer.

7. Are there any DIY tips for addressing OBDII code P2122 in a 2018 GMC Sierra?

- While basic inspections can be done, it is recommended to have a qualified mechanic diagnose and repair the issue to ensure proper resolution.

8. Will resetting the trouble codes fix OBDII code P2122 in a 2018 GMC Sierra?

- Resetting the codes may temporarily turn off the Check Engine light, but if the underlying issue is not addressed, the code is likely to reappear.

9. How much does it typically cost to fix OBDII code P2122 in a 2018 GMC Sierra?

- The cost can vary depending on the specific cause of the issue and labor rates, but it may involve expenses for sensor replacement, wiring repairs, and diagnostic fees.

10. Can weather conditions affect OBDII code P2122 in a 2018 GMC Sierra?

- Extreme weather conditions, such as excessive heat or moisture, can potentially impact sensor performance and contribute to the occurrence of this code.