Tech Tip – Headlights – We’ve found it best practice that when replacing a failed headlight bulb, to replace both at the same time. Bulbs are typically of the same age and with today’s “Daytime Running Lights” most headlights are on anytime the engine is running, so they wear out much quicker. Replacing both bulbs at the same time will often save you from a repeat visit a short time later when the bulb on the other side of the car fails. We’ve found this especially true of the “H-7” bulbs used in the majority of Audi, BMW, Mini, Mercedes, Volvo and VW autos, service life for these bulbs can be as short as 12-18 months due to the design and demands of the daytime running light system.

There are exceptions to this rule, one would be with the HID or Xenon bulbs. HID bulbs last much longer, and while we generally do replace those individually for cost reasons, replacement in pairs is ideal. Pair replacement is recommended as when the HID bulbs age, the color temperature of the light shifts from a white to a more bluish tint. If only one bulb is replaced, there will be a noticeable difference in color between the two headlights, and a corresponding compromise in light output. White light is preferable as it provides greater light output, and hence road illumination.