MB Medic Mercedes-Benz Repair Guides, Service, How To DIY
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When the high-beam light bulb in your Mercedes-Benz burns out, you need to replace it with the correct bulb type and wattage rating recommended by the manufacturer. Changing a burned out bulb is a short job. Headlight high-beam bulb failure can happen over time due to the age of the bulb. It is recommended that you replace both lights at the same time for two main reasons. You will have matching headlights in brightness and color. The second reason is that both bulbs have the same hours on them, so the one that still works is usually not far behind.
IMPORTANT: Avoid touching the light bulb glass with your hands.
WHAT YOU NEED
- H7 55W High Beam Light Bulb Buy on Amazon
How to change a high beam headlight bulb
There is not much room behind the headlight, so it is worth reading the steps through before you start rather than working it out with your hand in the gap.
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- Open the hood by pulling the hood release under the dash on the driver’s side.
- Pull the hood catch and lift the hood.
- Locate the back of the headlight.
S430 S500 Headlight - Remove the plastic cover from the back of the headlight assembly. Press the two plastic tabs together to remove the headlamp cover.
- Open the hood by pulling the hood release under the dash on the driver’s side.
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- Remove the electrical connector from the high-beam halogen-type light bulb.
High beam bulb and connector at the back of the headlight - Pull the old bulb out of the socket and fit the new bulb. Make sure it sits properly in the recess and that the tabs line up, because a bulb that is not seated square will not aim where the reflector expects it to.
- Remove the electrical connector from the high-beam halogen-type light bulb.
- Reinstall the electrical connector and the headlight cover in reverse order.
Why the glass must stay clean, and what to do if you touch it
The warning near the top of this page is worth a reason. A halogen bulb runs hot enough that anything on the quartz envelope bakes into it, and a fingerprint leaves oil and salt behind that forms a hot spot once the lamp is lit. The glass expands unevenly around that spot, which is how a brand new bulb fails in weeks rather than years. Handle it by the metal base or through the paper sleeve it came in.
If you do touch it, you do not need another bulb. Wipe the glass with a cloth dampened with isopropyl alcohol and let it dry fully before switching the lights on. The same applies to a bulb that has been dropped on a dusty bench.
Check it works before the cover goes back
The old cover and the connector are quick to refit and awkward to remove again, so prove the bulb first. With the new bulb in and the connector on, switch the ignition on and flick the high beams, then look at the front of the car from a few feet away. Both sides should light evenly. The page is right that twenty feet back is the better check for matching brightness, and that is worth doing once the covers are on.
If the new bulb does nothing, it is almost never the bulb. Pull the connector off and look at it: the usual causes are a connector that was not pushed fully home, a bulb not rotated into its locked position, or corrosion on the contacts. A bulb that lights and then goes out again shortly afterwards is worth checking at the fuse and the ground rather than replacing a second time.
Note: The headlight bulb must fit snugly in the headlight socket. If it is not seated properly the beam will not project where it should. You can verify this by turning on the light and looking at the headlights from 20 feet away. Both headlights should be the same brightness.
Applicable Models: S430 S500 S55 CL500 CL600 Chassis: W220 W215 Years: 1998 1999 2000 2001 2002 2003 2004 2005 2006
Before you buy parts, scan every control module, not just the engine. It shows the root fault behind the warning lights and tells you whether the problem is still active. See how to do a full health check.
