Luxury Headlamps

Why Xenon?

Lamps that use electrical arcs – lightning is an electrical arc, for example – have been around since before the lightbulb was invented. Carbon arc lamps were used in factories and as street lamps because they were so bright compared to gas lights. Later, arc lamps were used in movie projectors and search lights. Striking an arc continuously in a high-pressure bulb of xenon gas produces a bright, slightly blue light. A xenon arc lamp doesn’t erode its electrode quickly like a carbon arc lamp, so a xenon arc lamp can last for many thousands of hours of operation. Keeping the arc hot – many thousands of degrees hot – requires driving a high voltage through the lamp, a voltage higher than the 12 volts provided by a car’s battery. To achieve this voltage, a device called a “ballast” is used. Xenon headlamps can be much brighter than conventional halogen bulbs. Xenon headlamps also are more expensive than conventional halogen headlamps, partly because they are more complex and difficult to manufacture, and partly because they require special “ballast” electronics to make them work. Thus, in 2002 when my Lexus was built, xenon headlamps were a sign of luxury; they carried a cache that said, “I can afford the fanciest technology in my headlights” or something to that effect.

Why replace the bulbs?

At 188,500 miles, it looks like the Lexus still had its original low-beam headlamps. The brightness of the headlights seemed lacking, the bulbs pulsed when they were first energized, and I was concerned about how much it would cost to replace headlamps – as well as how complex it might be to do so.

It turns out that replacing a xenon headlamp in a Lexus LS430 is just about as simple as replacing a regular halogen bulb. I’ve heard claims on the Internet that people have been charged $200 to replace a headlamp – not including the cost of the part – because of the alleged complexity of replacing the bulbs.

Hella D2R 4300K headlamps are standard equipment and are available for less than $40 a piece at the time of this writing. $40 is a lot of money for a headlamp, and they must be replaced in pairs for best results. Typical halogen bulbs cost $20 to $25 per pair, so the Lexus’ headlamps are 4 times as expensive as standard halogen bulbs. Fortunately, xenon bulbs do last a long time. The picture below shows the box for a new Hella bulb and an original bulb taken out of the car on the right.

Replacement

This simple maintenance job requires only basic tools as follows:

• Phillips #2 and flat-blade screwdrivers.
• 10mm socket and socket wrench

The steps are as follows:

1. Disconnect the negative battery terminal.
2. Remove the plastic cover on right side.
3. Remove junction box cover on left side.
4. Remove fasteners from relay box on left side and swing out of the way over the open junction box from step #3.
5. Unscrew the back cap of the headlight assembly behind each low-beam bulb.
6. Twist the silver-colored connector counterclockwise, and pull it off of the back of the bulb.
7. Release the bulb hold-down clips by pushing the clip rings toward the front of the car.
8. Remove the old headlamp bulb.
9. Insert new headlamp bulb aligning the notch in the bulb base with the notch in the headlight assembly.
10. The rest of the steps are the reverse of disassembly.