How to Install HID Coversion Kit on Mercedes-Benz

Many Mercedes-Benz cars still come with halogen light bulbs. The halogen bulbs can be easily upgraded to HID (Xenon) headlights for brighter light and a more modern look. HID headlights give you better visibility and make driving at night safer. If HID low beams are not standard on your Mercedes-Benz, you can always get an aftermarket HID Conversion Kit. We recommend getting a kit that is ERROR-FREE and SLIM Design. You need an Error Free kit to avoid Low Beam Defective on your instrument cluster. If the HID kit uses 55W, you shouldn’t get error messages on the instrument cluster.

Top Rated – Best HID Conversion Kits for Mercedes-Benz. 

1. HID Conversion Kit H7 Error Free Slim – Best Selling on Amazon
2. Conversion Xenon Kit for Mercedes-Benz Slim Design on eBay (eBay link)

One of the best HID Kits for Mercedes-Benz, with great reviews from MB owners, is the MTEC HID Conversion Kit (eBay link) on eBay. The kit is easy to install, has authentic ballast and bulb, and works great on MB cars.  The downside of this kit is that it’s more expensive than most HID kits you find online.

You can choose any color that you like for the HID bulbs. We would recommend either a 5000k which is white or 6000k, which is slightly blue. If you go higher than that, the light turns blue at 8000k, and at 12000k, the light output is more of a purple color. The problem with the blue and purple light is that the visibility is reduced at that light spectrum. The choice is yours.

Instructions on how to upgrade Mercedes-Benz light to HID Xenon

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The following instructions are for installing HID lights on a W204, but these instructions are similar to other Mercedes-Benz cars without HID headlights. That’s because Mercedes-Benz used H7 halogen light bulb, and the mounting of the bulb is similar in other models such as E-Class, CLK-Class, ML-Class, CLS-Class, C-Class, SL-Class, etc.

Besides an HID Conversion Kit, electrical tape, a flat screwdriver, and a razor blade.

IMPORTANT NOTES:

• Installing the ballast inside the headlight can cause damage to the headlight assembly. Only install your HID this way if your ballast doesn’t produce too much light. Keep the ballast outside for a safe installation. Watch the video below to install the ballast outside the headlight assembly.
• Installing HID Conversion Kit can void your Mercedes-Benz warranty.
• The only HIDs that are DOT approved are the ones that come factory installed on new vehicles. There are no HID conversion kits that are DOT approved. Therefore HID conversion kits are for off-road, racing, and show car use.

Step 1 – Open the Hood

Start by opening up the hood. The hood release is on the driver’s side, underneath the dashboard.

Step 2 – Access the back of the headlight

Remove the cap from the back of the headlight assembly. To remove the cap from the back of the Mercedes-Benz headlight assembly, you must twist it counterclockwise.  You may want to wear gloves as you perform this upgrade.

Step 3 – Remove the old bulb

The bulb can be easily removed by twisting it a few degrees. Pull out the H7 halogen light bulb. Remove the electrical connector from the headlight and pull the H7 bulb out of the socket.

Step 4 – Install the HID

For a clean install, we will insert the ballast inside the headlight. This way, we avoid drilling holes in the headlight assembly. Use a Double Sided Tape such as 3m to place on the bottom of the ballast. Once you do that, insert the ballast inside the headlight housing and make sure it is secure. If your ballast gets very hot, you could risk damaging the headlight assembly with this method. You may want to test your ballast before installing it to ensure it doesn’t get too hot. You could also install the ballast outside the headlight, but you will need to drill holes in that case. It would be best if you were careful when handling these light bulbs, and also, don’t touch the ballast or bulbs when the lights are on.

Step 5 – Make wire connections

You must insert the wires through the metal clip that locks the bulb in place. To do this, you will need to remove the rubber piece.

In our case, we cut out the rubber piece. We don’t need the rubber piece since we install the ballast inside the headlight. If you plan on installing the ballast outside the headlight, you will need this rubber piece and will need to drill holes in the headlight assembly.

Step 6 – Make the Ballast Connection

Now plug in the HID Xenon Bulb to the HID kit. The wires are specifically designed so that they can not be mixed up. Check out a picture from our installation. Shown out of the headlights to demonstrate how the wiring should be set up.

Step 7 – Install HID Bulb

Install the H7 HID Xenon bulb into the headlight assembly. This can be tricky because you can’t see the socket. Here are some pictures that should help you install the H7 HID bulb.

Step 8 – Connect to stock H7 socket

Now you need to feed 12-volt power to the ballast. Connect the two wires from the ballast to the H7 plug you removed from the halogen light bulb. Go ahead and try your new lights.

Video – DIY HID Xenon Install: Mercedes-Benz C-Class 250/350 2007-2014

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If you plan on installing the ballast outside the headlight assembly, you may follow the following video helpfully. Besides installing the ballast outside the headlight assembly, the H7 bulb clip is a different design on this C-Class.

 

Frequently Asked Questions

HID Conversion Kit Problems

Certain HID Conversion Kits may not play well with Mercedes-Benz electrical systems. If you purchase a low-quality kit, you may find that the lights flicker or flash if you turn them on when the engine is on.

Will an HID Conversion Kit Void my Warranty

If your car is still under warranty, making unapproved upgrades like installing an aftermarket HID kit could void your warranty. Check with your MB dealer to verify your car is still under warranty.

What is HID?

HID stands for High-Intensity Discharge. HIDs use a high voltage charge of electricity from the ballast to arc between two electrodes inside a bulb full of different gases.

How long will my HID bulb last?

HID bulbs last around 5000 hours.

How much power will the HID Conversion Kit use?

HID Conversion Kits use ballasts that draw 35 watts of power. Mercedes-Benz halogen bulbs draw at least 55 watts. The HID Conversion Kit does draw slightly more power at start-up.