Headlight beam shooting out 90° to the car

[Stately]

Hello, this problem literally developed overnight for me and I have no idea how or why. I have a 2014 Fiesta sedan, and the left headlight beam “leaks” a sliver of light out 90° to the car. I was on the highway, and I was illuminating the car beside me. Most of the light still goes forward, but that slit really distracts me, probably because it wasn’t there before. I attached a picture that shows me nowhere near the front of the headlight and still in the bright portion of the beam. The right headlight doesn’t shine there at all.

 

[econoboxrocks]

I would try removing and reinstalling the headlight. This video shows you how.

The bulb might be out of place. You can check that with the light taken out.

 

[Stately]

I would try removing and reinstalling the headlight. This video shows you how.

The bulb might be out of place. You can check that with the light taken out.

Awesome, thank you. Anything in particular I should look for when the light is out? I removed just the bulb earlier but it didn’t make a difference

 

[Handy Andy]

The light may be from loss of the Lens hood, lampshade the low-beam bulb uses to confine the beam and the light to the cup the reflector so it can focus-stay the light from the beam, forward and not blind or wash out any way of seeing into the fog on a foggy night because the beam may be aimed OK, the lampshade it uses has fallen out of it's holder. That makes the bulb omnidirectional so it's bright light shines out all over 360 degrees.

Look to see if you can find that headlights lampshade - it may have fallen towards the turn signal amber light towards the front inside light in the headlamp assembly.

 

[Stately]

Yes! Ok, so that’s pretty much exactly what I played around with yesterday, removed the headlight and really took a good look. The lampshade was solid and intact, and aligned with its little pin in a hole. It just seems like the shade has to move aft more, because it’s not fully shielding the filament. A few months ago I did replace the bulbs but it wasn’t an issue until this week so no leads there. I tried the old (working) bulb to see if maybe the filaments were a bit longer in the new ones? And it didn’t make a difference.
I haven’t driven in the dark since I removed the headlight, but I did throw a couple washers under the lampshade attachment screw so that I could shim it to move back. It helped a decent amount as far as measuring the leaking light on my shirt, but there’s still a sliver. I’m hoping that when I drive at night the remaining sliver will be insignificant enough that I don’t notice it.
Thanks for getting back to me, it’s the little things that really are irritating.

 

[Handy Andy]

If you can, carefully, see if the lampshade itself is tilted forward in the holder.

There have been times where lamps have been changed and the shade gets pressed forward into the housings open space making it too far out and not providing the cover needed to keep the filament from leaking out around it - use a small hook tool with some length to see if you can pull it back into alignment - else if that slit of light is acceptable, then you're all set!

Good job!

Throwing this in this post so I can find it later...


The above is the LEFT side headlamp from a 2018 Fiesta - many that own older headlamps may not be able to see this detail due to the abrasion and scratches the surface lens cover suffers during normal everyday use and fading from sunlight.

The Marks are for helping to align the lamp to the parabolic mirror - both the High and Low beams are "offset" in their holder to let the mirror they are housed in, reflect the light properly at the right angle.



But, in hopes to help others, the parabolic reflector is similar to a concave mirror - only it uses the headlamps filament - positioned in a specific stationary spot, to deliver a focused beam.

To allow for greater shape of light aim and it's appearance in pattern - the reflector is shaped and uses forms of the different patterns of the concave shape to offset and augment the effectiveness of the point-source light to make the shine more efficient and effectively aimed to offer better visibility in various little to no-light situations.

The Lampshade itself is for the light to be bounced and sent out using the mirror - and because of the styling of the vehicle - the lamps are offset and headlamp shape to the fender- the design compromises this so they do a best fit for shape and function.