The P2320: Ignition Coil ‘G’ Secondary Circuit code indicates a problem in the secondary circuit of Ignition Coil ‘G’. This secondary circuit is responsible for delivering high voltage to the spark plug to ignite the air/fuel mixture in the engine’s combustion chamber. Problems in this circuit can lead to misfires and poor engine performance, which can be caused by a faulty ignition coil, wiring issues, or faulty connectors.
P2320 – Quick Overview
Code | Information |
---|---|
Meaning | P2320: Ignition Coil ‘G’ Secondary Circuit Issue |
Is it serious? | Yes, issues in the ignition coil secondary circuit can lead to weak or no spark, resulting in misfires, poor engine performance, and possible engine damage over time. Immediate attention is recommended. |
Possible causes | – Issues in the ignition coil ‘G’ secondary circuit – Faulty ignition coil – Wiring or connector problems |
How to diagnose? | – Inspect and test the ignition coil ‘G’ secondary circuit – Check wiring and connectors – Replace faulty ignition coil if needed |
P2320 Meaning
The P2320: Ignition Coil ‘G’ Secondary Circuit code indicates an issue in the high voltage portion of the ignition system for Ignition Coil ‘G’. The secondary circuit is responsible for transforming the lower voltage from the primary circuit into the high voltage needed for spark plug operation. If the secondary circuit has issues—such as a broken ignition coil, faulty wiring, or connector problems—the result will be poor spark production, leading to misfires and compromised engine performance.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any additional related codes. This can help provide more information about possible broader ignition or engine issues that need addressing. | OBD-II Scanner |
Inspect Ignition Coil ‘G’ | Visually inspect Ignition Coil ‘G’ for signs of physical damage such as cracks, burns, or corrosion. Such damage indicates that the coil is malfunctioning and affecting the secondary circuit. | Flashlight, Safety Gloves |
Test the Secondary Circuit of Ignition Coil ‘G’ | Use an ignition coil tester or ohmmeter to measure the resistance in the secondary winding of Ignition Coil ‘G’. Compare the readings with manufacturer specifications to ensure the coil is functioning properly. | Ohmmeter, Coil Tester |
Inspect Spark Plug Connected to Coil ‘G’ | Inspect the spark plug connected to Ignition Coil ‘G’ for fouling, wear, or damage. A compromised spark plug can place excessive load on the secondary circuit, leading to ignition coil failure. Replace if necessary. | Spark Plug Wrench, Replacement Spark Plug |
Inspect Wiring Leading to Coil ‘G’ | Inspect the wiring connected to Ignition Coil ‘G’ for damage such as frayed wires, broken insulation, or corrosion. Damaged wiring can cause improper voltage delivery in the secondary circuit. | Flashlight, Multimeter |
Check Connectors for Faults | Inspect all connectors leading to and from Ignition Coil ‘G’ to ensure that they are clean, securely connected, and free from corrosion or bent pins. Poor connections can lead to intermittent or weak signals. | Connector Cleaner, Flashlight |
Verify Grounding of Ignition Coil | Ensure that the ignition coil is properly grounded. A poor ground can cause insufficient secondary voltage and lead to improper ignition coil performance. Clean and secure the grounding point. | Multimeter, Hand Tools |
Test Coil Voltage Output | Use an oscilloscope or coil-on-plug tester to verify the coil’s voltage output. Ensure the voltage output to the spark plug is sufficient for efficient combustion. | Oscilloscope, Coil-on-Plug Tester |
Replace Faulty Components if Necessary | Replace any defective ignition coils, connectors, or wiring to ensure that the secondary circuit functions properly. Use OEM components to ensure compatibility and reliability. | Replacement Parts, Hand Tools |
Clear the Code and Test Drive | After completing repairs, clear the P2320 code using an OBD-II scanner. Start and test drive the vehicle to monitor ignition performance and verify that the problem has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure that the P2320 code has not returned. If the code persists, additional diagnostics focusing on the ECM and deeper ignition system components may be necessary. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)