Safety Dictates Changing Headlamps in Pairs

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Safety Dictates Changing Headlamps in Pairs

Just as it makes sense to replace both tires on the same axle or to replace both lower ball joints at the same time instead of simply replacing one worn part, when one headlamp fails, it makes sense to replace both at the same time. This provides optimum driving safety for the customer and improves your shop’s bottom line as well.

The new Philips safety campaign, dubbed CHIPS (Change Headlamps In Pairs), is built around this overall theme: “Don’t compromise on safety... change in pairs. Two new headlamps are safer than one.” The campaign is aimed at encouraging motorists and their service technicians to replace headlight bulbs in pairs, whenever they need to replace a bulb due to damage, failure, or when one of the bulbs starts to get dim due to age.

Motorists tend to only replace the bulb that has burned out or is failing. This is not advisable because replacing just one failed bulb can result in an unbalanced or unpredictable headlight beam and potentially present a safety risk.

The call to replace important auto parts in pairs is not a new one. Professional automotive technicians and driving safety advocates alike are constantly recommending that tires, brakes, shocks and wiper blades should be replaced in pairs to make sure the vehicle is properly balanced and functioning safely. Lighting needs to be treated in the same manner for customer satisfaction and driving safety.

Why replace light bulbs?

Why should you replace light bulbs when they get old? The answer is simple: Headlight bulbs age with use and the light output diminishes over time. The filament becomes fragile and starts to deteriorate.

During operation, small particles of the tungsten filament break away and attach to the inside of the burner, darkening the inside of the glass. These particles then burn off and turn into a gas that mixes with the bulb’s original gas fill mixture, further reducing the light output.

At the end of a typical service life, headlight bulbs will likely be projecting a much shorter and less powerful light beam than when they were new. The lighting output can be reduced by as much as 33%. Eventually, the filament with break in two and the bulb will fail.

From a driver’s point of view, this is a critical safety concern.

Why change in pairs?

Changing bulbs in pairs also makes good sense from an efficiency point of view.

By installing new bulbs on both right and left sides instead of replacing only the single failed lamp, the customer will have the issue handled in one visit, eliminating the need for them to come back and reducing the risk of the other headlight bulb failing when the customer is out on the road.

Halogen bulbs vs. Xenon HID

Halogen bulbs are the most commonly used type, while Xenon HID (high intensity discharge) bulbs are becoming increasingly featured on newer vehicles.

Halogen bulbs offer a typical lifetime of about 400 hours, while Xenon HID bulbs last approximately 3,000 hours.

Xenon HID bulbs also provide a more natural light and superior illumination (1,200 lumens for Halogen and 3,000 lumens for Xenon HID).

Regardless of the type, replacing bulbs in pairs is the recommended approach. If only one bulb is replaced, the customer may notice a dramatic difference in right vs. left side illumination.

Critical statistics

At night a typical driver’s visual acuity is naturally reduced by up to 70%. Statistics show that almost half of traffic fatalities happen at night and that much of the blame falls on reduced driver vision. That’s why it is so important to make sure that both headlamps are working properly so they can be as effective as possible.

Headlight maintenance is often overlooked, but properly maintained headlights can go a long way toward improving driver visibility at night.

As part of your overall safety check of a vehicle that enters your shop, be sure to also check the headlights to make sure they are functioning properly and effectively.

The Philips campaign is intended to create additional awareness of the need for lighting maintenance and will provide an opportunity for shops to increase revenue by promoting lighting safety.

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