2004 Lincoln LS Headlight Assembly

Your Lincoln LS headlight assembly provides you with visibility and the ability to drive at night and during inclement weather. It is an essential safety system, which, when not working properly, may lead you to various road accidents. Here are some problems you may encounter with your headlight assembly and how to troubleshoot them:

Only one headlight works

If only one headlight works, the other bulb may have burned out, since the bulbs have a limited number of hours in their useful life. This is also affected by the amount of vibration the car receives when driving. In this particular situation, the thin tungsten filament inside the bulb may have burned out. Another reason, in case you find the bulb is not burned out, is corrosion. Inspect the electrical connections-the socket and the connecting wires-for any sign of rust and corrosion. Check also if there are any wires that might have gotten loose over time.

Fluctuating headlight brightness

If both headlights are working but the brightness of the bulbs change when you step on the accelerator, you will need to check the charge of the battery using a digital multimeter while the engine is idling. It should read 13.5 to 14.5 volts. If it reads less than 13 volts, you may have a bad alternator or a slipping alternator drive belt.

Condensation from leaks

Over time, the headlight assembly can begin to leak and allow moisture and other contaminants into the inner side of the lenses where the bulbs are. This can damage the bulbs and cause them to burn out sooner than they ought or even create a short. Aside from this, the moisture inside the lenses can block out useful light and cause the Lincoln LS headlight assembly to poorly illuminate the road ahead. Check the seals around each opening, especially around the bulb sockets, if they have hardened or flaked out so you can replace them as necessary.

Dull headlight lens covers

If you have an older Lincoln LS model, you may encounter dull and milky-white headlight lens covers. This is caused by the harmful UV rays of the sun as they beat down on the plastic material of the lenses. This process breaks down the plastic and forms a film that can even be yellowish in color. Such discoloration can also extend below the surface of the headlight housing-a clear sign that you need to replace it with a new one.