AutoCodes – GMC – P2321 2016 GMC Sierra

P2321 2016 GMC Sierra Code - Ignition Coil 8 Control Circuit Low Voltage

Quick Answer

The ignition system on this engine uses ignition coils with integrated power transistors. Common causes include Faulty Ignition Coil 8, Ignition Coil 8 harness is open or shorted, Ignition Coil 8 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: P2321 2016 GMC Sierra indicates Ignition Coil 8 Control Circuit Low Voltage.
Common causes: Common causes include Faulty Ignition Coil 8, Ignition Coil 8 harness is open or shorted, Ignition Coil 8 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 396

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 25, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2321 2016 GMC Sierra Description

The ignition system on this engine uses ignition coils with integrated power transistors. The Engine Control Module (ECM) controls the spark event for each cylinder through individual ignition coil control circuits. When the ECM commands the ignition control circuit On, electrical current flows through the primary winding of the ignition coil, creating a magnetic field. When a spark event is requested, the ECM commands the ignition control circuit Off, interrupting current flow through the primary winding. The collapsing magnetic field created by the primary winding induces a high voltage in the secondary winding, which is connected to the spark plugs. The Diagnostic Trouble Code (DTC) will be set when the control circuit commanded by the ECM state does not match the actual state.

OBDII Code P2321 2016 GMC Sierra - Ignition Coil 8 Control Circuit Low Voltage - AutoCodes.com — P2321 2016 GMC Sierra Code - Ignition Coil 8 Control Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P2321 2016 GMC Sierra?

Faulty Ignition Coil 8
Ignition Coil 8 harness is open or shorted
Ignition Coil 8 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P2321 2016 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2321 2016 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 P2321 2016 GMC Sierra code?

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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 P2321 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P2321 in a 2016 GMC Sierra?

- Common symptoms include rough idling, engine misfires, loss of power, and illuminated Check Engine Light.

2. What does the OBDII code P2321 in a 2016 GMC Sierra indicate?

- The code indicates a low voltage condition in the control circuit of ignition coil 8.

3. What are the possible causes of OBDII code P2321 in a 2016 GMC Sierra?

- Possible causes include a faulty ignition coil, damaged wiring or connectors, a defective PCM, or a weak battery.

4. How can I diagnose the OBDII code P2321 in my 2016 GMC Sierra?

- Diagnose the code by inspecting the ignition coil, checking the wiring for damage, testing the connectors, and scanning the PCM for other related codes.

5. Can I continue driving my 2016 GMC Sierra with OBDII code P2321 present?

- It is not recommended to drive the vehicle with this code as it can lead to further engine damage and potential safety hazards.

6. How can I repair OBDII code P2321 in my 2016 GMC Sierra?

- Repair options include replacing the faulty ignition coil, repairing damaged wiring or connectors, resetting the PCM, and ensuring proper battery voltage.

7. Is it possible to clear OBDII code P2321 in a 2016 GMC Sierra without fixing the issue?

- Clearing the code without fixing the underlying issue may temporarily turn off the Check Engine Light, but the problem will likely reoccur.

8. How much does it typically cost to repair OBDII code P2321 in a 2016 GMC Sierra?

- The cost of repair can vary depending on the exact cause, but it may range from $100 to $300 for parts and labor.

9. Can a DIY enthusiast fix OBDII code P2321 in a 2016 GMC Sierra?

- DIY enthusiasts with automotive repair experience and the necessary tools can attempt to fix the issue, but professional help is recommended for accurate diagnosis and repair.

10. How long does it take to repair OBDII code P2321 in a 2016 GMC Sierra?

- The repair time can vary based on the specific cause and repair process, but it may take anywhere from 1 to 3 hours to complete the repair.