P1370 – OBD-II DTC

OBD-II DTC P1370 – Ignition Coil Secondary Circuit Failure

DTC P1370 meaning

DTC P1370 refers to an “Ignition Coil Secondary Circuit Failure.” This diagnostic trouble code indicates that the engine control module (ECM) has detected a malfunction in the secondary circuit of the ignition coil. The secondary circuit is responsible for generating the high voltage needed to create a spark at the spark plugs, which is essential for proper engine operation.

DTC P1370 symptoms

Common symptoms associated with DTC P1370 may include:

• Engine misfires
• Rough idling
• Decreased engine performance
• Difficulty starting the engine
• Illuminated check engine light

DTC P1370 causes

Several factors can lead to the triggering of DTC P1370, including:

• Faulty ignition coil
• Wiring issues in the ignition coil circuit
• Defective spark plugs
• Faulty ECM
• Corroded or loose connectors

DTC P1370 seriousness

DTC P1370 is considered a serious issue as it can lead to engine misfires and poor performance. If left unaddressed, it may result in further engine damage, increased emissions, and reduced fuel efficiency. It is advisable to diagnose and repair the issue promptly to maintain optimal vehicle performance.

How to diagnose DTC P1370

To diagnose DTC P1370, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the ignition coil and its wiring for visible damage or corrosion.
• Check the spark plugs for wear or fouling.
• Test the ignition coil’s resistance using a multimeter.
• Examine the ECM for any signs of malfunction.

How to fix DTC P1370 step-by-step instructions

To fix DTC P1370, follow these step-by-step instructions:

1. Disconnect the negative battery terminal to ensure safety.
2. Inspect and repair any damaged wiring or connectors in the ignition coil circuit.
3. Replace the faulty ignition coil if necessary.
4. Change any worn or fouled spark plugs.
5. Reconnect the battery terminal and clear the DTC using an OBD-II scanner.
6. Start the engine and monitor for any reoccurrence of the code.

How to erase DTC P1370

To erase DTC P1370, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the ignition without starting the engine.
• Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
• Confirm the action to clear the trouble codes.
• Disconnect the scanner and start the engine to ensure the code does not return.

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