NGK U5553-49646 Ignition Coil 49646 Pencil Coil [Single Output Type]

【NGK U5553-49646 Ignition Coil 49646 Pencil Coil [1-output type] 】
■Product Description
Role of the Ignition Coil
In internal combustion engines using spark plugs, a high voltage of 20,000 to 35,000V is required to cause a discharge 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 spark plug 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 components.

Specifications
High-voltage generation principle of ignition coils
Although there are various types of ignition coils, differing in appearance and the 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) switches the igniter to the ON state, allowing current to flow into the primary coil. This generates a bundle of magnetic lines of force called magnetic flux in the core (iron core) that serves as the axis of the primary coil, and the core (iron core) becomes 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, due to electromagnetic induction*, 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 spark plug gap, igniting the air-fuel mixture (gasoline + air).
*A coil has the property of generating voltage when the magnetic flux passing through it changes. This voltage generation phenomenon is called electromagnetic induction.
Since the voltage generated in a coil increases in proportion to the number of turns, ignition coils increase the winding of the secondary coil to generate high voltage.
Type: Pencil coil [1-output type]
Since ignition coils are directly attached to each spark plug, spark plug wires are not necessary. This is currently the most commonly adopted type by automotive manufacturers.

■Image Precautions
*Images are for illustration purposes only. Products with different sizes and colors are included. Product design and specifications are subject to change without notice. Please be aware of this.

■Precautions
1. Always stop the engine before inspecting or replacing.
2. Please check for oil adhesion or leaks around the plug hole. Oil adhesion or leaks can cause malfunctions.
3. Perform inspection and replacement according to the service manual of each automobile manufacturer.
4. Handle connectors carefully when attaching and detaching. Damaging the connector part can lead to poor conductivity.
5. Do not use a product that has been dropped, as impact can cause cracks or damage to internal components.
6. Please use the correct part number ignition coil specified in this manual.
7. Do not use the ignition coil in this manual for purposes other than its intended use.
8. When storing, avoid high temperatures and humidity.
9. When the engine check (MIL) lamp illuminates, before (or after) replacing the ignition coil, always clear (reset) the diagnostic (self-diagnosis/OBD) error code according to the service manual, etc. Failure to clear the error code may lead to problems such as the engine check lamp not turning off.