NGK U5281-49497 Ignition Coil 49497 Pencil Coil [1-Output Type]

【NGK U5281-49497 Ignition Coil 49497 Pencil Coil [1-Output Type] 】
■ Product Description
Role of Ignition Coils
In internal combustion engines that use spark plugs, a high voltage of 20,000 to 35,000V is required to generate a spark in the combustion chamber during the compression stroke. An ignition coil is a type of transformer that converts the 12V battery voltage into the high voltage necessary for the spark plug to discharge. It basically consists of a primary coil, a secondary coil, and a core (iron core), and epoxy resin is filled into the case to ensure insulation between these parts.

Specifications
High Voltage Generation Principle of Ignition Coils
Although there are various types of ignition coils, differing in external shape and number of output terminals, the principle of high voltage generation is the same for all. The primary coil is connected to the battery via an igniter (switch). First, the ECU (engine control unit) turns the igniter ON, causing current to flow through the primary coil. This generates a bundle of magnetic field lines called magnetic flux in the core (iron core) that acts as the axis of the primary coil, making the core (iron core) an electromagnet. Then, when the ECU determines the engine ignition timing, it switches the igniter to the OFF state, stopping the current to the primary coil. As a result, the core (iron core) ceases to be an electromagnet, and the magnetic flux inside the core (iron core) also disappears. When the magnetic flux inside the core (iron core) suddenly disappears, a high voltage is generated in the secondary coil, which shares the same core (iron core) as its axis, through electromagnetic induction* and in proportion to the turns ratio of the primary and secondary coils. The high voltage generated in the secondary coil causes a spark to jump across the gap of the spark plug, igniting the air-fuel mixture (gasoline + air).
*Coils have the property of generating voltage when the magnetic flux passing through them changes. This phenomenon of voltage generation is called electromagnetic induction.
Furthermore, since the voltage generated in a coil increases in proportion to the number of turns, ignition coils generate high voltage by increasing the number of windings in the secondary coil.
Type: Pencil Coil [1-Output Type]
Pencil coils attach directly to each spark plug, eliminating the need for plug wires. This is currently the most commonly adopted type by automobile manufacturers.

■ Image Disclaimer
*Images are for illustration purposes only. They may include products of different sizes or colors. Product design and specifications are subject to change without notice. We appreciate your understanding.

■ Precautions
1. Always stop the engine before inspecting or replacing parts.
2. Please check for any oil adhesion or leakage around the plug hole. Oil adhesion or leakage can cause malfunctions.
3. Inspect and replace parts according to the service manual of each automobile manufacturer.
4. Please handle connectors carefully when attaching and detaching. Damage to the connector can lead to poor conductivity.
5. Do not use products that have been dropped, as dropping or impacting them may cause cracks or damage to internal components.
6. Please use the correct part number of ignition coil as specified in this document.
7. Do not use the ignition coil mentioned in this document for any purpose other than its intended use.
8. When storing, avoid high temperatures and high humidity.
9. When the engine check (MIL) lamp illuminates, be sure to clear (reset) the diagnostic (self-diagnosis/OBD) error code according to the service manual or similar, either before or after replacing the ignition coil. Failure to clear the error code may lead to problems such as the engine check lamp not turning off.