AutoCodes – GMC – P2303 2018 GMC Sierra

P2303 2018 GMC Sierra Code - Ignition Coil 2 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 2, Ignition Coil 2 harness is open or shorted, Ignition Coil 2 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: P2303 2018 GMC Sierra indicates Ignition Coil 2 Control Circuit Low Voltage.
Common causes: Common causes include Faulty Ignition Coil 2, Ignition Coil 2 harness is open or shorted, Ignition Coil 2 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 244

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 P2303 2018 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 P2303 2018 GMC Sierra - Ignition Coil 2 Control Circuit Low Voltage - AutoCodes.com — P2303 2018 GMC Sierra Code - Ignition Coil 2 Control Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P2303 2018 GMC Sierra?

Faulty Ignition Coil 2
Ignition Coil 2 harness is open or shorted
Ignition Coil 2 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P2303 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2303 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 P2303 2018 GMC Sierra code?

Need more information on how to fix the P2303 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P2303 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 P2303 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P2303 in a 2018 GMC Sierra?

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

2. What causes the OBDII code P2303 in a 2018 GMC Sierra?

- The code P2303 typically indicates a problem with the ignition coil 2 control circuit experiencing low voltage, which can be caused by a faulty ignition coil, wiring issues, or a failing engine control module.

3. How can I diagnose the issue causing OBDII code P2303 in my 2018 GMC Sierra?

- Diagnostic steps may include checking the ignition coil 2 for proper operation, inspecting the wiring for any damage or loose connections, and using a multimeter to test voltage levels in the circuit.

4. Can a DIY enthusiast repair OBDII code P2303 in a 2018 GMC Sierra?

- Depending on your skill level, you may be able to replace the faulty ignition coil 2 or repair any damaged wiring yourself. However, if you are unsure, it is recommended to seek professional assistance.

5. Is it safe to continue driving my 2018 GMC Sierra with OBDII code P2303 present?

- It is not advisable to drive the vehicle with code P2303 active, as it can lead to further engine issues and potential damage if left unresolved. It is recommended to address the problem promptly.

6. How much does it typically cost to repair OBDII code P2303 in a 2018 GMC Sierra?

- The cost of repairing OBDII code P2303 can vary depending on the specific issue causing the code, but it may range from $100 to $300 for parts and labor.

7. Are there any preventive measures to avoid OBDII code P2303 in a 2018 GMC Sierra?

- Regular maintenance, such as inspecting and replacing ignition components at recommended intervals, can help prevent issues like code P2303 from occurring.

8. Can a bad spark plug cause OBDII code P2303 in a 2018 GMC Sierra?

- While a bad spark plug may contribute to engine performance issues, OBDII code P2303 specifically relates to the ignition coil 2 control circuit experiencing low voltage.

9. Will resetting the Check Engine Light resolve OBDII code P2303 in a 2018 GMC Sierra?

- Simply resetting the Check Engine Light will not fix the underlying issue causing code P2303. It is important to diagnose and address the root cause of the problem.

10. How long does it typically take to repair OBDII code P2303 in a 2018 GMC Sierra?

- The repair time for OBDII code P2303 can vary based on the extent of the issue and the availability of parts, but it may take anywhere from 1 to 3 hours at a repair shop.