Primer On Quartz Iodine (QI) Headlights

BMW Headlights If you’ve been a reader of the Roundel for any length of time, no doubt you have noticed occasional references to quartz iodine (QI) lights. You may have wondered what they are, what they can do for your BMW 2002, and how to install them. This article is designed to answer those questions.

Since the mid 1930’s, cars sold in the U.S. have been saddled with totally inadequate lights sealed beams. The specifications of these lights have not been upgraded since that time although our road system, our style of driving, and the number of cars on the road have all changed radically. In Europe, by contrast, quartz iodine lights are the standard rather than the exception. There is a glimmer of hope in the U.S., however: the Federal Government is relaxing its stand against such lights; the State of Washington recently became the first state to actually legalize them; and many states such as Massachusetts simply overlook their use even though they are technically illegal. In many states today one can safely install these lights without fear of being bothered. Even California, one of the toughest anti-QI states, is relaxing its stand against them because it realizes how good they are.

The accompanying photos [ referenced to original article ] gives an idea of the advantages of quartz lights versus sealed beams. I will not go into the technical aspects of the two types of lights. The principal physical difference is that sealed beams are just that; when the light fails, you go to your nearby dealership, gas station, or auto parts store and simply buy a replacement. Better still, you always carry a replacement of each type of light in your trunk. Quartz lights, by comparison, use renewable bulbs for their illumination and have much different lenses. The lenses vary depending upon the application of the light. When a quartz light fails, you remove the light socket and change the bulb. As with sealed beamed, a replacement bulb for each type of light should always be carried in the car.

Drivers who have switched to quartz lights use them as replacements for the sealed beams, as add-on driving lights for remote areas where extra light is needed, and as fog lights for bad weather or cornering. The easiest type of light to replace is the sealed beam. On virtually any BMW, one can obtain access to these by removing the plastic grill which is held in place with machine screws (be careful not to drop the machine screws into the sheet metal of the front of the car where you can lose them). After the grill is out you will find three more machine screws holding the light retaining bezel in place (a bezel is a piece of metal that fits over the light housing). Remove two of these three and loosen the third, and the bezel will swing away. You can then simply lift out the light and unplug it.

Different lights have different numbers of prongs on the plug, so make sure you are replacing apples with apples. This is easy when you have only a two-headlight system but a little more complicated when you have four headlights. Most manufacturers give complete directions with the QI lights you buy (through Roundel ads or elsewhere), and you should not have any trouble if you read the directions carefully. Simply plug in the quartz replacement light and replace the screws in reverse order of disassembly of the bezels and grills. Turn on your headlight switch and check for proper operation, and if necessary adjust the beams. That’s all there is to quartz light replacement.

One further thing you might like to try is 100 watt bulbs for the high beams of a four-headlight set. These will really burn the paint off the car in front of you when you flash at it, but their price is higher and their life is shorter. Bear in mind, though, that the actual number of hours during which you will operate the high beams is not that great in most urban areas. I’ve had mine for four years and the original bulbs are still going strong.

Driving lights are a good addition for those who live in rural areas; or for rallyists, racers, and anyone else who needs an extra amount of candlepower when driving. Such lights are ordinarily mounted either above or below the bumpers, depending upon your preference and the way they look on your car. With pre-impact-type bumpers, there are kits available to mount the lights without drilling holes in the chrome (consult a BMW dealer’s parts book). For the aluminum impact-type bumpers, however, it’s just as easy to drill through and mount the lights per manufacturer’s instructions above or below the bumper. If you mount them below, BMW sells brackets that protect them from curb damage, bottoming out, and the like.

When you get into driving or fog lights, this may or may not involve extra wiring, depending upon the car you own. Later model BMWs are pre-wired for fog or driving lights, and the wires usually terminate near the battery. If this is the case, you need only add a switch on the dashboard (available to match your existing switches), a light relay in the fuse box, and fuses for each light you add to protect yourself in the event of wire or light difficulty. If you are interested in the specifics of wiring lights in a 530i, see my article on 530i accessories in the June 1976 Roundel.

If your car is not pre-wired, you must add a switch, a relay, fuses, and of course, wiring through the firewall to connect all these. The basic idea of it is that power flows from the hot lead to the relay, and from the relay through fuses to the light. The relay is grounded through the dashboard switch, so the circuit is not complete until the switch is activated. It is also possible to do it the other way around wire the hot lead through the switch but this involves more wiring and is not recommended. Wherever you run wires through sharp metal corners, try to protect them with wire grommets or, at the very least, tape so that these corners will not rub the insulation off wires and cause them to short.

Fog lights are designed to help you drive in fog, rain, snow and other bad weather. They’re also very good as cornering lights because they project a lateral beam to the sides of the car rather than a strong beam ahead of the car. Installation of fog lights is identical to that of driving lights, so follow the above instructions. A few people have added one fog light and one driving light and have wired them separately. This has the advantage of a less cluttered look, but is not particularly effective in bad weather although the one driving light will certainly increase illumination when the high beams are turned on.

If you can get away with it from the standpoint of state regulations, I strongly recommend the use of quartz lights. Once you’ve tried them, you’ll realize that sealed beam lights are totally inadequate. Qls don’t blind oncoming drivers, either, if they are properly aimed, although some people may still think you have your high beams on simply because they project such an intense beam downward. With winter coming and shorter days ahead, now is the time to switch to quartz lights. You won’t regret changing.

Author: Dick Neville

The advantages of QI headlights over sealed beam are obvious, however, the beginner should also realize these advantages do not come cheaply. A pair of 7″ replacement lights with bulbs cost anywhere between thirty and fifty dollars depending on manufacturer and dealer. Bulbs alone run between three and ten dollars.

Pay particular attention to the manufacturers instructions with regard to handling QI bulbs. They must never be touched by your fingers or you will risk almost immediate failure. Ed.


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