AutoCodes – GMC – P2303 GMC

P2303 GMC 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 GMC 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 580

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 Jul 31, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2303 GMC 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 GMC - Ignition Coil 2 Control Circuit Low Voltage - AutoCodes.com — P2303 GMC Code - Ignition Coil 2 Control Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P2303 GMC?

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 GMC?

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 GMC 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 GMC code?

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

Need Help with the Code?

Get the P2303 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P2303 2014 GMC Sierra — Ignition Coil 2 Control Circuit Low Voltage
P2303 2015 GMC Sierra — Ignition Coil 2 Control Circuit Low Voltage
P2303 2016 GMC Sierra — Ignition Coil 2 Control Circuit Low Voltage
P2303 2017 GMC Sierra — Ignition Coil 2 Control Circuit Low Voltage
P2303 2018 GMC Sierra — Ignition Coil 2 Control Circuit Low Voltage

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 GMC Code

1. What are common symptoms of OBDII code P2303 GMC (Ignition Coil 2 Control Circuit Low Voltage)?

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

2. What can cause OBDII code P2303 GMC to trigger?

- The code may be triggered by a faulty ignition coil, damaged wiring or connectors, or issues with the Engine Control Module (ECM).

3. How can I diagnose the cause of OBDII code P2303 GMC?

- Diagnose by inspecting the ignition coil, checking for damaged wiring or connectors, and using a scan tool to monitor voltage readings.

4. Can driving with OBDII code P2303 GMC cause further damage to the vehicle?

- Continuing to drive with this code may lead to more severe engine issues, reduced fuel efficiency, and potential damage to the catalytic converter.

5. How can I repair OBDII code P2303 GMC (Ignition Coil 2 Control Circuit Low Voltage)?

- Repair options include replacing the faulty ignition coil, repairing damaged wiring or connectors, or reprogramming the ECM if necessary.

6. Are there any preventive measures to avoid OBDII code P2303 GMC in the future?

- Regular maintenance, such as timely spark plug and ignition coil replacements, can help prevent issues that may trigger this code.

7. Can I drive my vehicle with the Check Engine Light on due to OBDII code P2303 GMC?

- It is not recommended to drive with the Check Engine Light on, as unresolved issues can lead to more significant problems and potential safety hazards.

8. How much does it typically cost to repair OBDII code P2303 GMC at a mechanic or dealership?

- Repair costs can vary depending on the specific cause of the code, but it may range from $100 to $300 for parts and labor.

9. Is OBDII code P2303 GMC a common issue in GMC vehicles?

- This code can occur in various GMC models, especially as vehicles age or if maintenance is neglected.

10. Can a DIY enthusiast with basic automotive knowledge fix OBDII code P2303 GMC themselves?

- Depending on the specific cause, some DIY enthusiasts may be able to address the issue by replacing the ignition coil or repairing wiring, but professional diagnosis and repair may be necessary in some cases.