AutoCodes – GMC – P1682 2018 GMC Sierra

P1682 2018 GMC Sierra Code - Ignition 1 Switch Circuit 2

Quick Answer

There are 2 ignition 1 voltage circuits supplied to the Engine Control Module (ECM). Common causes include Faulty ignition switch, Ignition Switch harness is open or shorted, Ignition Switch 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: P1682 2018 GMC Sierra indicates Ignition 1 Switch Circuit 2.
Common causes: Common causes include Faulty ignition switch, Ignition Switch harness is open or shorted, Ignition Switch 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 479

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 Aug 11, 2022

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

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

Code P1682 2018 GMC Sierra Description

There are 2 ignition 1 voltage circuits supplied to the Engine Control Module (ECM). The first ignition circuit is provided by the powertrain relay, through a fuse. This ignition 1 voltage circuit supplies power to all the internal ECM circuits associated with the throttle actuator control (TAC) operation. The second ignition 1 voltage circuit is supplied by the run/crank relay through a fuse and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition 1 voltage circuits, DTC P1682 will set.

OBDII Code P1682 2018 GMC Sierra - Ignition 1 Switch Circuit 2 - AutoCodes.com — P1682 2018 GMC Sierra Code - Ignition 1 Switch Circuit 2

What does this mean?

What are the Possible Causes of the DTC P1682 2018 GMC Sierra?

Faulty ignition switch
Ignition Switch harness is open or shorted
Ignition Switch circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P1682 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

There is a Factory Service Bulletin for the following Chevrolet models:
2016-2018 Chevrolet Silverado 1500
2019 Chevrolet Silverado LD
Dead Battery / P1682 P129D P10E4 P2535 / Crank No Start

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1682 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.

Need more information about the P1682 2018 GMC Sierra code?

Need more information on how to fix the P1682 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1682 2018 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.

Frequently Asked Questions about P1682 2018 GMC Sierra Code

1. What does OBDII code P1682 in a 2018 GMC Sierra mean?

The code P1682 in a 2018 GMC Sierra indicates a problem with the Ignition 1 Switch Circuit 2.

2. What are the common symptoms of OBDII code P1682 in a 2018 GMC Sierra?

Common symptoms of P1682 may include issues starting the vehicle, intermittent stalling, and problems with electrical components.

3. What are the possible causes of OBDII code P1682 in a 2018 GMC Sierra?

Possible causes of P1682 include a faulty ignition switch, wiring issues, poor electrical connections, or a malfunctioning ignition switch circuit.

4. How can I diagnose the source of OBDII code P1682 in my 2018 GMC Sierra?

To diagnose P1682, you may need to perform a thorough inspection of the ignition switch, check the wiring for any damage, and test the circuit for continuity using a multimeter.

5. Can I still drive my 2018 GMC Sierra with OBDII code P1682 present?

It is not recommended to drive your GMC Sierra with the P1682 code present, as it may lead to potential safety hazards and further damage to the vehicle.

6. How can I repair OBDII code P1682 in my 2018 GMC Sierra?

Repairing P1682 may involve replacing the faulty ignition switch, repairing damaged wiring, ensuring proper electrical connections, and clearing the trouble code with an OBDII scanner.

7. Will disconnecting the battery reset OBDII code P1682 in a 2018 GMC Sierra?

Disconnecting the battery may temporarily reset the code, but if the underlying issue causing P1682 is not fixed, the code is likely to reappear after some time.

8. Can a DIY enthusiast fix OBDII code P1682 in a 2018 GMC Sierra?

Depending on your level of automotive expertise, a DIY enthusiast may be able to diagnose and repair P1682 by following online guides or service manuals. However, if unsure, it's best to consult a professional mechanic.

9. How much does it cost to repair OBDII code P1682 in a 2018 GMC Sierra at a mechanic?

Repair costs for P1682 can vary based on the specific issue and labor rates in your area. It's advisable to get quotes from different mechanics to compare prices before proceeding with the repair.

10. Is OBDII code P1682 a serious issue in a 2018 GMC Sierra?

While P1682 may not always indicate a critical problem, it should be addressed promptly to prevent potential safety risks and avoid further damage to the vehicle's electrical system.