1. Introduction
Thank you for choosing CHOPDARK D4S HID to LED Headlight Bulbs. This product is designed to upgrade your vehicle's existing HID lighting system to a more efficient and brighter LED solution. These bulbs offer enhanced visibility, a longer lifespan, and improved energy efficiency compared to traditional HID bulbs. Please read this manual thoroughly before installation and use to ensure proper operation and safety.

Image: Overview of CHOPDARK D4S LED bulbs highlighting key features such as brightness, plug-and-play installation, long lifespan, power efficiency, and IP68 waterproof rating.
2. Safety Information
Always prioritize safety during installation and operation. Improper installation can lead to electrical hazards or damage to your vehicle.
- Ensure the vehicle's engine is off and the battery is disconnected before beginning installation.
- Wear appropriate personal protective equipment, including gloves and eye protection.
- Avoid touching the LED chips directly, as oils from your skin can reduce their lifespan.
- Do not look directly into the illuminated LED bulbs, as the intense light can cause eye strain or damage.
- If you are unsure about any part of the installation process, consult a qualified automotive technician.
3. Package Contents
Your CHOPDARK D4S HID to LED Headlight Bulbs package includes:
- 2 x CHOPDARK D4S LED Headlight Bulbs
4. Specifications
| Bulb Type | D4S (compatible with D4R, D4C) |
| Power | 110W (55W per bulb) |
| Brightness | 30000 Lumens (15000 Lumens per bulb) |
| Color Temperature | 6500K Cool White |
| LED Chips | Latest Big size LED chips, 2x15 large particles |
| Cooling System | 2 Thermally Conductive Copper Tubes, Copper Substrate, Large Rear Radiator, High-Speed Fan (12000RPM) |
| CANbus Compatibility | Built-in high power smart driver, error-free for 90% of vehicles. External decoders may be required for certain models. |
| Protection Rating | IP68 (Waterproof, Dustproof, Cold proof, High temperature resistance) |
| Item Weight | 5.3 ounces |
| Package Dimensions | 4.53 x 4.02 x 1.93 inches |
5. Setup and Installation
Installation of these LED bulbs requires careful attention. If you are not confident in performing the installation yourself, it is recommended to seek professional assistance.
Important Note:
For optimal heat dissipation, these D4S bulbs are equipped with a large radiator at the rear. Some vehicle models may require an extended dust cover during installation to accommodate this. Please ensure you have the correct extended dust cover for your vehicle if necessary.
Video: A step-by-step guide demonstrating the installation process for CHOPDARK LED D2S/D2R/D4S/D4R bulbs into a headlight assembly.
Installation Steps:
- Access Headlight Housing: Locate your vehicle's headlight assembly. Depending on your vehicle model, you may need to remove other components to gain access.
- Remove Dust Cover: Open or remove the dust cover from the rear of the headlight housing.
- Remove Original HID Bulb: Rotate the original HID bulb counterclockwise to unlock it, then carefully remove it from the housing. Disconnect any wiring.
- Open Circlip: Locate and open the circlip (retaining clip) that holds the bulb in place.
- Separate LED Bulb Plate: Gently twist and remove the mounting plate from the new CHOPDARK LED bulb. This plate will be installed first.
- Install LED Bulb Plate: Insert the LED bulb plate into the headlight housing, aligning the gap and bump for correct orientation. Secure it by closing the circlip.
- Connect Wiring: Connect the plug from the LED bulb's driver to the vehicle's original HID ballast socket. Ensure a secure connection.
- Insert LED Bulb Body: Insert the main body of the LED bulb into the installed mounting plate. Push firmly until it clicks into place. Ensure the wire faces downward for proper alignment and beam pattern.
- Secure and Test: Once the bulb is securely in place, reattach the dust cover (using an extended version if required). Test the lights to ensure they function correctly before reassembling any removed vehicle components.

Image: Visual guide for the plug-and-play installation of the D4S LED bulbs, detailing the removal of the bulb base, insertion into the headlight housing, and final connection.
6. Operating Instructions
Once installed, the CHOPDARK D4S LED headlight bulbs operate like your vehicle's standard headlights. Simply turn on your vehicle's lighting system to activate them.
- Beam Pattern: These bulbs are designed to provide a standard and safe beam pattern, ensuring clear visibility without excessive glare for oncoming traffic.
- Brightness: Experience significantly increased brightness and a crisp 6500K cool white light for improved night driving visibility.

Image: Illustration comparing low beam and high beam performance, demonstrating the improved light distribution and intensity of the LED bulbs.

Image: Technical diagrams depicting the light projection for both low beam and high beam settings within a projector headlight system.
7. Maintenance
The CHOPDARK D4S LED bulbs are designed for durability and a long lifespan with minimal maintenance. Follow these guidelines to ensure optimal performance:
- Cleaning: If necessary, gently wipe the bulb's glass surface with a clean, dry, lint-free cloth. Avoid using abrasive cleaners or solvents.
- Inspection: Periodically check the bulbs and wiring for any signs of damage or loose connections.
- Heat Dissipation: Ensure the rear radiator area of the bulb remains clear of obstructions to allow for proper airflow and heat dissipation. This is crucial for the longevity and performance of the LED bulbs.

Image: Detailed illustration of the bulb's internal cooling mechanisms, including copper heat pipes, a high-speed fan, and a large finned heat sink.

Image: Demonstration of the bulb's IP68 protection, indicating its resilience against rain, sand, snow, and fog.
8. Troubleshooting
If you encounter issues with your CHOPDARK D4S LED bulbs, refer to the following common problems and solutions:
- Bulbs are flickering or dashboard warning lights appear:
These bulbs feature a built-in smart CANbus driver compatible with most vehicles. However, some specific vehicle models may require additional external CANbus decoders, error eliminators, or resistors to resolve flickering or dashboard warnings. Contact your vehicle manufacturer or an automotive specialist for compatibility information. - One or both bulbs are not lighting up:
Check all electrical connections to ensure they are secure and properly seated. Verify that the vehicle's power supply to the headlights is functioning correctly. Inspect the bulb for any visible damage. - Reduced brightness or short lifespan:
Ensure that the bulb's cooling system (radiator and fan) is not obstructed and has adequate space for heat dissipation. Overheating can lead to reduced performance and premature failure. Confirm that the correct extended dust cover is used if required for your vehicle.
9. Warranty and Support
CHOPDARK is committed to providing high-quality products. For any warranty claims, technical assistance, or support inquiries, please contact CHOPDARK customer service through the retailer where you purchased the product. Please have your purchase details and product model information available when contacting support.