1. Introduction
Thank you for choosing the Mould King 12025 Remote Control Steam Locomotive building block set. This manual provides detailed instructions for the assembly, operation, maintenance, and troubleshooting of your model train. Please read this manual carefully before beginning assembly and retain it for future reference.
This set allows you to construct a detailed replica of the SNCF 231 steam locomotive, complete with remote control functionality, LED lighting, and simulated smoke. The set includes 3898 pieces, offering a challenging and rewarding building experience.
2. Safety Information
- This product contains small parts and is not suitable for children under 3 years old due to choking hazards.
- Adult supervision is recommended during assembly and operation, especially for younger users.
- Keep all packaging materials away from children to prevent suffocation.
- Do not expose electronic components to water or excessive moisture.
- Ensure batteries are inserted with correct polarity. Do not mix old and new batteries or different types of batteries.
- Dispose of used batteries responsibly according to local regulations.
- Avoid direct contact with the simulated smoke output, as it may contain harmless but irritating substances.
3. Package Contents
The Mould King 12025 set includes the following main components:
- 3898 building block pieces for the locomotive, coal wagon, and luxury passenger wagon.
- Remote control unit.
- Lithium battery for the train.
- XL motors (2 sizes).
- R104 track sections to form a circular track (170cm x 69cm).
- LED lighting group.
- Simulated smoke unit.
- Detailed assembly instructions (in French, refer to the provided manual for visual guidance).
4. Assembly Instructions
Assembly of the Mould King 12025 is a multi-step process. Follow the included detailed French instruction manual for piece-by-piece guidance. The following sections provide a general overview and important tips.
4.1. Unpacking and Sorting
Carefully unpack all bags of building blocks. It is highly recommended to sort the pieces by color and type to facilitate the assembly process. The set contains many small parts, so ensure a clean and organized workspace.
4.2. Locomotive Chassis Assembly
Begin by assembling the main chassis of the locomotive. This forms the foundation for the entire model. Pay close attention to the placement of axles and gears for smooth operation.

Image 1: Fully assembled Mould King 12025 steam locomotive and passenger car on tracks.
4.3. Motor and Electronic Component Installation
Install the XL motors and the lithium battery compartment into the designated sections of the locomotive. Route all wires carefully to avoid pinching or damage. Connect the LED lighting group and the simulated smoke unit according to the instructions. Ensure all connections are secure.
Note: Customer feedback indicates that wiring for lighting can be delicate. Exercise caution to prevent wires from breaking or short-circuiting during installation.

Image 2: Detailed view of internal components, including connection points and cabin controls.
4.4. Wagon Assembly
Assemble the coal wagon and the luxury passenger wagon. These wagons are designed to be detachable and can be combined in various ways. The tops of the wagons can be opened to access internal details or electronic accessories. Wagons connect via magnetic attraction.

Image 3: Interior view of the passenger wagon and how the roof can be removed.
4.5. Track Assembly
Assemble the R104 track sections to form a complete circular track. Ensure all track pieces are securely connected to create a stable and continuous path for the train.

Image 4: Dimensions of the assembled circular track (170cm x 69cm).
5. Operating Instructions
5.1. Remote Control Setup
Insert the required batteries into the remote control unit (batteries for remote control are not included in the set). Power on the remote control and the train's main power switch (usually located on the locomotive's underside or within the coal wagon).
5.2. Pairing the Remote Control
Follow the specific pairing instructions in your detailed French manual to connect the remote control to the train. Typically, this involves holding a button on both the train and the remote until a connection is established (indicated by a light or sound).
5.3. Basic Train Functions
- Movement: Use the joystick or directional buttons on the remote control to move the train forward or backward. Adjust speed as desired.
- LED Lighting: Activate or deactivate the LED lights using the designated button on the remote.
- Simulated Smoke: If the smoke unit is filled with appropriate liquid (not included) and connected, use the remote control to activate the simulated smoke feature.
- Sound Effects: Some models may include sound effects. Refer to your detailed manual for specific controls.

Image 5: The Mould King 12025 locomotive navigating a curved section of track.
6. Maintenance
6.1. Cleaning
To clean the building blocks and train model, use a soft, dry cloth. For stubborn dirt, a slightly damp cloth can be used, but ensure no moisture enters the electronic components. Do not use harsh chemicals or abrasive cleaners.
6.2. Storage
When not in use, store the train set in a cool, dry place away from direct sunlight and extreme temperatures. Disassemble wagons if desired for compact storage. Remove batteries from both the train and remote control if storing for extended periods to prevent leakage.
6.3. Track Care
Keep the tracks clean and free of dust or debris to ensure optimal electrical contact and smooth train movement.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Train does not move. |
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| LED lights do not work. |
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| Simulated smoke not produced. |
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| Train is fragile or parts detach easily. |
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8. Specifications
| Model Name | Orient Express SNCF Type 231 Locomotive à Vapeur |
| Model Number | Mould King 12025 |
| Brand | MOULD KING |
| Number of Pieces | 3898 |
| Product Dimensions (L x W x H) | 118.5 x 12.7 x 8.9 cm (Locomotive) |
| Track Dimensions (L x W) | 170 x 69 cm (Circular layout) |
| Material | Plastic |
| Power Source | Battery (Lithium battery for train, separate batteries for remote control) |
| Control Method | Remote Control |
| Recommended Age | Adult (or 8+ with supervision, despite manufacturer's 0-8 year recommendation which seems incorrect for this complex set) |
| UPC | 705736700407 |
| Manufacturer Reference | WX12025-LYF |
9. Warranty and Support
Mould King provides an after-sales guarantee for this product. Each piece undergoes machine picking and three tests before packaging to ensure completeness.
Missing Parts: If you find any missing pieces in your set, please contact Mould King customer support directly. Missing parts will be sent to you free of charge.
For further assistance or inquiries, please refer to the contact information provided with your purchase or visit the official Mould King website.