Quick Info
Model
452
Estimated Cost
€50 – €100
Difficulty
Intermediate
Time Required
1 Hour
Safety Notes
High Voltage: HID ballasts generate high voltage (up to 23,000V) to ignite the bulbs. Never touch the wiring or the bulb while the lights are switched on.
Bulb Handling: Do not touch the glass of the HID bulbs with your bare fingers. Oil from your skin can cause the glass to crack when it heats up. Use gloves or a clean cloth.
Battery Safety: It is highly recommended to disconnect the battery before starting any electrical work to prevent short circuits.
Secure Mounting: Ensure ballasts are mounted away from moving parts and heat sources to prevent melting or vibration damage.
Step-by-Step Guide
Introduction
The Smart Roadster is a design icon, but its original factory lighting—particularly the fog lights—can feel outdated and dim by modern standards. Standard halogen bulbs (H7) in the low beam light housings often lack the range and "cutoff" required for truly effective night driving. Upgrading to HID (High-Intensity Discharge) Projectors is one of the most rewarding DIY projects for any Roadster owner.
Unlike a simple LED bulb swap which often scatters light and blinds other drivers, a projector housing uses a specialized lens to focus the light into a precise beam. This gives you a sharp horizontal cutoff, much like high-end modern cars, ensuring all that extra light stays on the road where you need it. In this guide, we will walk through the process of accessing the fog light housings behind the front panels, managing the wiring for the ballasts, and ensuring a clean, waterproof installation that will make your night drives significantly safer and more enjoyable.
Accessing the Front Panels
To reach the fog lights, you need to open the front hood and loosen the front paneling. Use the Torx T25 and T15 tools to remove the screws securing the fog light surrounds and the top sections of the front bumper. This allows enough flexibility to pull the panel forward and access the rear of the light housings.
Removing the Factory Lights
Locate the factory light units. They are typically held in by three screws. Once the screws are removed, carefully pull the housing forward. Unplug the original H7 halogen connector from the back of the bulb.
Preparing the Projector & Bulb
Take your new HID H7 bulb and carefully insert it into the projector housing. Ensure the wire clip is securely snapped into place to hold the bulb steady. If your kit includes a rubber dust cap, ensure it is seated correctly to prevent moisture from entering the housing.
Wiring the Ballast
The HID system requires a ballast to regulate power. You will need to connect the wiring from the car’s original harness to the ballast, and then from the ballast to the new bulb:
Connection Logic: In this specific setup, you should connect the Brown wire to Black (Ground) and the Red wire to Red (Positive).
Ensure the "click" is felt on all waterproof connectors to guarantee a solid seal against the elements.
Mounting the Ballast
Find a flat, dry spot behind the front panel to mount the ballast. Use heavy-duty double-sided tape or zip ties to ensure it cannot move or rattle while driving. Common locations include the inner side of the front crash bar or the side of the headlight bucket.
Before putting all the screws back in, turn on your ignition and test the fog lights. Check that both sides ignite quickly and the color is consistent. Once confirmed, slide the housings back into place, tighten the screws, and re-secure the front panels.
