P0354 – OBD-II DTC

OBD-II DTC P0354 – Ignition Coil C Primary/Secondary Circuit Malfunction

DTC P0354 meaning

DTC P0354 refers to a malfunction in the ignition coil C primary/secondary circuit. This code indicates that the Engine Control Module (ECM) has detected an issue with the electrical circuit that powers the ignition coil responsible for firing the spark plugs in cylinder C. The ignition coil converts the battery’s low voltage into the high voltage needed to create a spark, which ignites the air-fuel mixture in the engine’s combustion chamber.

DTC P0354 symptoms

Common symptoms associated with DTC P0354 may include:

• Engine misfires
• Rough idling
• Decreased engine performance
• Increased fuel consumption
• Check Engine Light (CEL) illuminated
• Difficulty starting the engine

DTC P0354 causes

Several factors can lead to the triggering of DTC P0354, including:

• Faulty ignition coil C
• Open or short circuit in the ignition coil wiring
• Defective Engine Control Module (ECM)
• Poor electrical connections or corroded terminals
• Faulty spark plugs or ignition wires

DTC P0354 seriousness

DTC P0354 is considered a moderate to serious issue. If left unaddressed, it can lead to engine misfires, which may cause further damage to the engine and exhaust system. Additionally, prolonged misfiring can result in increased emissions and potential failure of emissions tests. It is advisable to diagnose and repair the issue promptly to maintain optimal engine performance and reliability.

How to diagnose DTC P0354

To diagnose DTC P0354, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0354 code.
2. Inspect the ignition coil C and its wiring for any visible damage or corrosion.
3. Check the electrical connections to ensure they are secure and free of debris.
4. Test the ignition coil C using a multimeter to check for proper resistance.
5. Inspect the spark plugs and ignition wires for wear or damage.
6. Check the ECM for any software updates or faults.

How to fix DTC P0354 step-by-step instructions

To fix DTC P0354, follow these steps:

1. Replace the faulty ignition coil C if testing indicates it is defective.
2. Repair or replace any damaged wiring or connectors associated with the ignition coil circuit.
3. Replace worn or damaged spark plugs and ignition wires as necessary.
4. Clear any stored trouble codes using an OBD-II scanner.
5. Test drive the vehicle to ensure the issue is resolved and the Check Engine Light does not reappear.

How to erase DTC P0354

To erase DTC P0354, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear Codes” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the engine to verify that the Check Engine Light is off.

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