1. Introduction
Thank you for choosing the BLALION Universal Car Rearview Mirror LED Turn Signal and DRL Light Strip. This product is designed to enhance vehicle visibility and safety with its dual-functionality: bright white daytime running lights (DRL) and dynamic yellow flowing turn signals. Featuring an ultra-thin, flexible design and high-quality LEDs, these light strips offer stable performance and a long service life. This manual provides essential information for proper installation, operation, and maintenance.
2. Features
- High Quality LEDs: Super bright and long-lasting illumination.
- Stable Performance: Built to strict quality control standards for reliable operation.
- Universal Compatibility: Suitable for all 12V vehicles with a built-in decoder for easy installation.
- Flexible Design: Soft circuit board allows installation on curved surfaces of rearview mirrors, with appropriate bending.
- Customizable Length: Light strip can be cut according to marked lines to fit specific installation needs.
- Dual Functionality: Provides white daytime running lights and dynamic yellow flowing turn signals.
3. Specifications
| Attribute | Value |
|---|---|
| Brand Name | BLALION |
| Model Name | C41974 / LED Side Mirror Turn Signal Lights |
| Item Type | Turn Signal |
| For Vehicle Brands/Model | Universal |
| Voltage | 12 V |
| Item Weight | About 44g/2pcs |
| Origin | Mainland China |
| Light Color | White and yellow |
| Length | 14cm (5.51inch) / 18cm (7inch) |
| Features | Length can be cut, Dynamic Car Rear Turn Signals, Streamer LED Auto Flow Lights, Universal Car LED Strip Light, Sequential Car Daytime Running Lights |
4. Package Contents
Depending on your order, the package includes:
- 1 or 2 x BLALION LED Strip Bar Set (14cm or 18cm length)
Please verify all components are present and undamaged upon opening the package.

Figure 1: BLALION LED strip lights and their application on a car rearview mirror.
5. Safety Information
- Always disconnect the vehicle's battery before performing any electrical work.
- Ensure all wiring connections are secure and properly insulated to prevent short circuits.
- Do not modify the product in ways not described in this manual.
- Keep the product away from excessive heat, moisture, and corrosive substances.
- Professional installation is recommended for optimal safety and performance.
6. Installation and Setup
The BLALION LED light strips are designed for universal fitment on 12V vehicles, typically installed on rearview mirrors.
6.1. Preparation
- Ensure the vehicle's ignition is off and the battery is disconnected.
- Clean the installation surface on the rearview mirror thoroughly to ensure proper adhesion.
- Determine the desired length and placement of the LED strip.
6.2. Customizing Length
The LED strip can be cut to your desired length. Locate the designated cut marks on the strip. Carefully cut along these lines. After cutting, it is crucial to seal the cut end with glass glue or silicone rubber to protect the internal components from moisture and damage.

Figure 2: LED strip with cut marks and sealing instructions.
6.3. Wiring Connections
The LED strip comes with three wires for connection:
- Black wire: Connect to the vehicle's negative (-) terminal or a suitable ground point.
- White wire: Connect to the vehicle's turn signal positive (+) wire.
- Red wire: Connect to the vehicle's positive (+) wire for daytime running lights (DRL).
Note: If only the turn signal (steering) function is required, the red wire can be disconnected.

Figure 3: Wiring diagram for the BLALION LED strip.
6.4. Mounting the LED Strip
- Carefully peel off the adhesive backing from the LED strip.
- Align the strip with the desired position on the rearview mirror.
- Press firmly along the entire length of the strip to ensure strong adhesion.
- Route the wires securely, ensuring they do not interfere with mirror movement or other vehicle components.
7. Operating Instructions
Once properly installed and wired, the BLALION LED light strips will operate as follows:
- Daytime Running Lights (DRL): When the vehicle's ignition is on and the DRL function is active (red wire connected), the LED strips will illuminate with a bright white light.
- Turn Signal Function: When the vehicle's turn signal is activated (white wire connected), the white DRL will switch off, and a dynamic yellow flowing light will appear, indicating the turn direction.
- Double Flash Effect: When the hazard lights are activated, both LED strips will display the dynamic yellow flowing light simultaneously.
Video 1: Demonstration of the LED strip lights' functions, including daytime running lights, start scan, yellow turn signal sync, water diversion effect, driving white light, double flash, ultra-thin design, and bending flexibility.

Figure 4: Car rearview mirror displaying yellow flowing turn signal light.

Figure 5: Car rearview mirror demonstrating the dynamic yellow flowing turn signal effect.
8. Maintenance
- Cleaning: Gently wipe the LED strips with a soft, damp cloth to remove dirt and debris. Avoid using harsh chemicals or abrasive materials.
- Inspection: Periodically check the wiring connections for any signs of wear, corrosion, or looseness. Ensure the adhesive remains secure.
- Sealing: If the strip was cut during installation, regularly inspect the sealed ends to ensure the sealant is intact and protecting the internal components.
9. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Lights not turning on | Loose or incorrect wiring, blown fuse, insufficient power. | Check all wire connections (positive, negative, turn signal). Verify vehicle's fuse for the relevant circuit. Ensure 12V power supply. |
| Incorrect light color or function | Incorrect wiring of white/red wires. | Double-check that the white wire is connected to the turn signal and the red wire to the DRL power source. |
| Lights flickering or dim | Poor connection, low voltage, damaged strip. | Inspect wiring for loose connections or corrosion. Test vehicle voltage. If the strip is damaged, it may need replacement. |
| Adhesive failing | Improper surface cleaning, extreme temperatures, old adhesive. | Re-clean surface and reapply with stronger automotive-grade adhesive tape or sealant. |
10. User Tips
- For a cleaner installation, consider routing wires through existing mirror housing gaps or using wire loom for protection.
- Test the lights thoroughly before finalizing all connections and reassembling any vehicle parts.
- When cutting the strip, use a sharp blade for a clean cut and apply sealant immediately to prevent moisture ingress.
11. Warranty and Support
For any questions, concerns, or technical support regarding your BLALION LED light strips, please contact the seller or manufacturer directly. Keep your purchase receipt as proof of purchase for any warranty claims.