---
title: "Mercedes C-Class Headlight Repair: W203 and W204"
description: "Mercedes C-Class headlight repair for W203 and W204 xenon units: new lens, cloudy projector glass cleaned, damp sealed out, LED running lights renewed."
url: https://headlightrepairshop.co.uk/models/mercedes-benz/c-class/
lang: en-GB
---

# Mercedes C-Class Headlight Repair (W203, W204)

Mercedes C-Class headlight repair on the W203 and W204 is mostly about xenon units that have aged: lenses gone yellow, projectors gone dim and seals that let the weather in. Each of those can be put right on your own headlight rather than a replacement from the dealer.

[Get a quote](https://headlightrepairshop.co.uk/get-a-quote/)[How it works](https://headlightrepairshop.co.uk/how-it-works/)

![Mercedes C-Class W204 xenon headlight on a stand, its lens gone yellow](https://headlightrepairshop.co.uk/img/models_mercedes-c-class-headlight-repair.webp)

## Which C-Class headlights are worth repairing

Both generations were sold with halogen or xenon headlights. A halogen C-Class unit is cheap enough new that repairing it seldom adds up, unless you want to keep the original for its own sake.

Xenon units are a different story. They cost far more to replace, and the faults below are all ones a bench repair handles.

Generations coveredW203 and W204, saloon and estate Headlight typesHalogen, xenon; LED running lights on later W204 xenon cars Common faultsYellowed lens, dim projector, water inside

![Xenon headlight on a test stand from behind with a new ballast, part of a Mercedes C Class headlight repair](https://headlightrepairshop.co.uk/img/models_mercedes-c-class-headlight-repair_xenon-ballast-test.webp)

## A fresh lens on a W203 or W204 xenon unit

As a Mercedes xenon design from before 2016, the C-Class unit is usually bonded with a sealant that softens under heat. Once warm, the yellowed or crazed lens comes away and the new one is set in a fresh bead of sealant.

The projector, bulb and reflector behind it are not disturbed. Lens work in general: [Headlight Lens Repair and Replacement](https://headlightrepairshop.co.uk/headlight-repair/lens-replacement/).

## When the xenon beam has gone weak

A C-Class whose xenon lights look tired, even with new bulbs, often has a smoky film on the glass at the front of the projector. Over the years the bulb gives off a little gas that settles there.

With the lens open, that glass is cleaned and the beam regains its brightness. It is worth asking about before buying another pair of bulbs.

## Condensation and running lights

Droplets that never dry out mean the lens joint has failed; the cure is a full reseal, not a hairdryer. On later W204 cars with an LED running light in the headlight, a strip that has dimmed or died is renewed inside the unit.

More on resealing and drying: [How to Remove Condensation From a Headlight](https://headlightrepairshop.co.uk/guides/remove-headlight-condensation/).

![Condensation inside a lit headlight lens at night](https://headlightrepairshop.co.uk/img/models_mercedes-c-class-headlight-repair_mist-lit-at-night.webp)

## C-Class headlight questions

### How do I tell whether my C-Class has xenon headlights?

Send a photo of the front of the car with the lights on. The unit type is clear from that, or from the sticker on the rear of the unit.

### Is the projector glass cleaned as part of a lens replacement?

It can be, since the headlight is already open. Mention dim light in your request and it will be included in your quote.

Back to [Mercedes Headlight Repair](https://headlightrepairshop.co.uk/models/mercedes-benz/). How long a C-Class unit is away is confirmed in your quote.

## Brighten up your C-Class

One photo in daylight and one at dusk with the lights on are ideal.

[Get a quote](https://headlightrepairshop.co.uk/get-a-quote/)