Recently, we’ve received quite a few questions from customers about the wiring setup of the TOYAN FS-L400 14cc Inline 4 Cylinder 4 Stroke Water-cooled Assembly Engine Model.

To make the installation process easier, we’ve put together this quick guide explaining the basic wiring connections for the engine. This tutorial should help both beginners and experienced model engine enthusiasts complete the setup more smoothly.

Understanding the CDI Ignition System

The CDI (Capacitor Discharge Ignition) system is a core ignition control component commonly used in small engines, motorcycles, and gasoline-powered model engines.

In engines like the TOYAN FS-L400 14cc Inline 4 Cylinder 4 Stroke Water-cooled Assembly Engine Model, the CDI system controls the ignition process through four key stages: energy storage, trigger detection, voltage boosting, and spark distribution.

This system ensures accurate ignition timing and stable engine operation.

Other CDI igniters operate on a similar principle.

The Four Key CDI Connections

The CDI ignition system typically uses four main connections, each serving a specific function.

1. Power Supply Wire

The power wire connects to a 2S–3S lithium battery (7.4V–11.1V).
This provides electrical power for the CDI unit and is the main energy source for the entire ignition system.

2. Ground Wire (Black)

The black ground wire must be securely connected to the metal engine casing.

This creates a stable electrical circuit and helps ensure:

• stable ignition voltage
• reduced electrical interference

• reliable spark generation

3. Hall Sensor Signal Wire

The Hall sensor is installed inside the distributor assembly and works together with a magnet mounted on the distributor shaft.

When the engine rotates:

• the magnet passes by the Hall sensor
• the sensor detects the magnetic field change
• a trigger signal is sent to the CDI module

This signal tells the CDI exactly when to fire the spark plug, ensuring accurate ignition timing.

4. High-Voltage Coil Control Wire

Once the CDI receives the trigger signal, it sends a high-energy pulse to the ignition coil.

The ignition coil then boosts the voltage from low voltage to tens of thousands of volts, which is required to generate the spark at the spark plug.

Complete CDI Ignition Process

The CDI ignition system operates through the following sequence:

1. Energy Storage

The lithium battery powers the CDI unit.
Inside the CDI, the voltage is processed and used to charge a high-voltage capacitor.

This capacitor stores electrical energy for the ignition event.

2. Trigger Detection

As the engine rotates:

• the distributor shaft spins
• the magnet passes the Hall sensor
• the Hall sensor sends a pulse signal to the CDI

This signal indicates that the engine has reached the correct ignition position.

3. Instant Discharge and Voltage Boost

When the CDI receives the trigger signal:

• an internal switch instantly activates
• the capacitor releases its stored energy
• a high-current pulse flows into the ignition coil

The ignition coil then converts this pulse into very high voltage.

4. Spark Distribution

The high-voltage electricity is sent to the distributor.

As the distributor rotor spins with the engine, it distributes the spark to each spark plug in the correct firing order:

1 – 3 – 4 – 2

Each spark plug ignites the air-fuel mixture in its cylinder, allowing the engine to produce power and run smoothly.

If you purchased the new starter kit, you should receive these.

Refer to the wiring diagram below

If you purchased the older starter kit, you should receive one of the two shown below.

Refer to the wiring diagram below

If you have any questions during installation or wiring, feel free to contact our support team. We’re always happy to help and will do our best to assist you.