Why Do Legacy and Outback Headlights Burn Out So Fast?

Outback and Legacy owners are seeing red. Well, technically they're not seeing anything and that's the problem. The 2011-2012 model years in particular seem to burn through an alarming number of headlights. Some owners have reported having to replace the bulbs three times within 36,000 miles.

And to make matters worse? Changing the lights is a major PITA. How bad can changing a light bulb be? Let's just say it's recommended you take off the front wheel and/or bumper first.

What Causes Car Headlight Bulbs to Burn Out? ∞

Light bulbs, whether they're in a Subaru or your house, are going to burn out eventually. But what are the factors that lead to a bulb's demise?

1. Let's get the most obvious reason out of the way first. The more you use your headlights, the quicker they'll burn out. I dare you to challenge me on this. But what's not always so obvious is how this ties into our next point.
2. Most modern cars come with daytime running lights (DRL), although DRL typically uses less power. Another safety feature is auto mode which detects when it's too dark and the lights come on (as the name suggests) automatically. Both are good for safety, but they also reinforces the 1st point.
3. When installing headlights, keep your grubby fingers off the bulb. The oils and dirt on your skin transfer to the bulb which then creates hot-spots and shortens the bulb's life considerably.
4. If you have a bumpy commute or live on a dirt road, the transferred vibration could cause the lights to bounce. Excessive vibration can break apart the delicate filaments inside the bulb.
5. Headlights are designed to work with a specific voltage, so any electrical surges can fry them like a good piece of catfish.

Why Do Outback and Legacy Headlights Fail Faster? ∞

So all headlights burn out, but the 2010-12 Outback and Legacy fail at a much higher rate. Some owners have to replace them every other month and there's a couple theories why.

1. Subaru's "auto mode" is much more aggressive than it has to be. A number of Subaru owners have said that the their "auto" lights are too sensitive. They come on when there's plenty of light in the sky or the driver passes under an underpass for a couple seconds.
2. There is a power spike somewhere in the Subaru electrical system. The bulbs need a specific voltage to work and even a small spike in voltage can fry the filaments. Could a defective alternator be surging the electrical system and causing the damage?
3. There are more complaints because the replacement process is so stupidly hard. Even if the bulbs burn out more often than not it wouldn't be the end of the world if each one required a trip to the dealership to get them replaced.

"I'm seriously getting tired of replacing the external headlights at a rate of nearly twice per year. Having to go through the wheel well makes it especially frustrating! – 2011 Outback owner in Michigan"

The Expired Warranty Enhancement Program ∞

In August 2016, Subaru started sending letters to owners about a Low Beam Headlight Halogen Headlamp Bulb Warranty Enhancement Program. Because succinctness is overrated.

This was a sign that Subaru was aware of the headlight problems.

While not a recall, the program extended the vehicle's original "new car limited warranty" for headlamp bulbs to 10 years from the warranty start date (regardless of mileage). It also confirmed that Subaru was aware of widespread premature headlight burn out in its 4th generation Outback and Legacy.

Owners who had previous repairs done were eligible for reimbursement with proper documentation. However, claims to the program had to be submitted by November 17, 2016.

So, where does that leave owners still having problems?

Headlight Burn Out Class-Action Lawsuit ∞

In May 2016, a 2011 Outback owner filed a proposed class-action lawsuit over headlight problems. The owner said it wasn't the first failure that prompted the action, but the nine times after that:

"The lawsuit says O’Neill purchased a new 2011 Subaru Outback and by the end of 2011, the left front headlight had failed followed by the right headlight in February 2012. A dealership replaced both headlights in the new car, but the plaintiff says the headlights continued to fail. According to the lawsuit, exterior lighting failed nine more times causing the plaintiff to pay $317.55. Most of the failures involved headlights, but on some occasions failures included side marker lights, parking lights, license plate lights and turn signal lights."

The lawsuit names the 2010-2011 Outback and says voltage surges pass through the system, causing the lights fail. The problem seems to be made worse when the lights are put in automatic mode.

For what it's worth, Subaru recommends you keep your lights in "auto mode."