CDI or Capacitor Discharge Ignition is an electronic ignition system used in engines to ignite the fuel. The 4 pin CDI wiring diagram is a schematic diagram that serves as a guide for the wiring of the CDI system in engines. CDIs are mostly found in small engines like motorcycles, ATVs, and dirt bikes. The 4 pin CDI system is one of the most popular systems used in these engines. In this article, we will discuss the 4 pin CDI wiring diagram and how to wire a CDI system.
What is a 4 Pin CDI?
A 4 pin CDI is an ignition system that has four wires coming out of it. The four wires are usually colored black, red, green, and yellow. The CDI system has two main parts, the stator and the CDI box. The stator is the part of the engine that generates the electrical power to charge the battery and power the electrical system. The CDI box is the electronic module that controls the ignition timing and the spark output.
The Function of Each Wire
The black wire is the ground wire. It is connected to the engine frame or chassis to provide a return path for the electrical current.
The red wire is the positive wire. It is connected to the battery or the electrical system’s positive terminal to supply power to the CDI box.
The green wire is the trigger wire. It is connected to the stator’s trigger coil or pick-up coil to send a signal to the CDI box that the engine is ready to fire.
The yellow wire is the output wire. It is connected to the ignition coil to produce a spark that ignites the fuel mixture in the engine.
How to Wire a 4 Pin CDI
The wiring of a 4 pin CDI is relatively simple. Here are the steps to follow:
Step 1: Disconnect the Battery
Before starting the wiring process, make sure to disconnect the battery to avoid any electrical shock or damage.
Step 2: Locate the Stator
The stator is usually located on the left side of the engine. It has two types of coils, the charging coil, and the trigger coil. Locate the trigger coil or pick-up coil and find the wires coming out of it.
Step 3: Identify the Wires
Identify the trigger wire and trace it back to the CDI box. Connect the green wire from the CDI box to the trigger wire. Then locate the charging coil wires and connect the black wire from the CDI box to the frame or chassis of the engine. Connect the red wire from the CDI box to the positive terminal of the battery or the electrical system.
Step 4: Connect the Output Wire
The yellow wire from the CDI box is connected to the ignition coil to produce a spark that ignites the fuel mixture. Locate the ignition coil and connect the yellow wire from the CDI box to the positive side of the coil. The negative side of the coil is usually connected to the frame or chassis of the engine.
FAQs
| Question | Answer |
|---|---|
| What is a CDI box? | A CDI box is an electronic module that controls the ignition timing and the spark output in an engine. |
| What does a CDI do? | A CDI controls the timing and the voltage of the spark that ignites the fuel mixture in the engine. |
| What happens if the CDI is faulty? | If the CDI is faulty, the engine may not start or may exhibit poor performance. It can also cause misfires or erratic running of the engine. |
| Can a CDI be repaired? | Some CDIs can be repaired, while others need to be replaced. It depends on the type and extent of the damage to the CDI. |
| What causes a CDI to fail? | A CDI can fail due to various reasons like overheating, moisture, electrical surges, or physical damage. |
Conclusion
The 4 pin CDI wiring diagram is a useful guide to help you wire a CDI system in engines. It is relatively simple to wire a 4 pin CDI system, and it is a crucial component of the engine’s ignition system. By following the steps outlined in this article, you can wire your CDI system correctly and ensure that your engine runs efficiently and smoothly.
