NGK U5222-48741 Ignition Coil 48741 Pencil Coil [1-output type]

【NGK U5222-48741 Ignition Coil 48741 Pencil Coil [1-Output Type]】
■Product Description
Role of Ignition Coils
In internal combustion engines using spark plugs, a high voltage of 20,000 to 35,000V is required to discharge electricity 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 is basically composed 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
While there are various types of ignition coils, differing in external shape, number of output terminals, etc., the high voltage generation principle 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 ON, allowing current to flow through the primary coil. This generates a bundle of magnetic field lines 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. Subsequently, when the ECU determines the engine ignition timing, it switches the igniter OFF, 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, initiating the combustion of 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.
Furthermore, 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]
Ignition coils are mounted directly on each spark plug, so spark plug wires are not necessary. This is currently the most commonly adopted type by automobile manufacturers.

■Image Disclaimer
*Images are for illustration purposes only. Includes products of different sizes and colors. Product design and specifications are subject to change without notice. Please understand.

■Precautions
1. Always turn off the engine before inspection or replacement.
2. Please check for any oil adhesion or leakage around the plug hole. Oil adhesion or leakage can cause malfunctions.
3. Perform inspection and replacement according to the service manual of each automobile manufacturer.
4. Please handle connector attachment and detachment carefully. Damaging the connector can lead to poor electrical conductivity.
5. Do not use dropped products, as dropping or impacting them may cause cracks or damage to internal components.
6. Use the correct part number ignition coil as described in this document.
7. Do not use the ignition coil described in this document for any purpose 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 codes according to the service manual or similar. Failure to clear the error codes may lead to problems such as the engine check lamp not turning off.