• Share:
How to Repair a Dim Headlight

Simply clean the ground connection to restore the brightness of dim headlights. And apply a little dielectric grease. Or replace the bulb if you see a gray/brown film on the inside of the glass.

By the DIY experts of The Family Handyman Magazine

Repair a dim headlight

If your car has a headlight that puts out about as much light as a flashlight with weak batteries, we’ve got two simple fixes for you.

Most DIYers think they’ve got a bad headlight switch or a bad connection in the power feed. But most dim headlights are caused by a corroded ground wire. Just trace the wiring harness from the back of each headlight assembly and see where it connects to the vehicle body. Clean it as described in the photo.

Another possibility is that as headlight filaments age, they deposit a gray/brown film on the inside of the bulb (See Photo). Over time, that coating can reduce visibility by almost 300 ft. If your headlights aren’t as bright as they used to be, yank one of the bulbs and look for gray or brown residue on the glass. If you find any, replace both bulbs now and get back to seeing more of the road.

Back to Top

Required Tools for this Project

Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.

    • Adjustable wrench
    • Wire brush

Required Materials for this Project

Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.

    • Dielectric grease

Comments from DIY Community Members

No comments on the article have been posted yet. Be the first to add your comment!

You will be required to log in or create an account to post a comment.

closeX

Add Your Comment

How to Repair a Dim Headlight

Please add your comment
closeX

Log in to My Account

Log in to enjoy membership benefits from The Family Handyman.

  • Forgot your password?
Don’t have an account yet?

Sign up today for FREE and become part of The Family Handyman community of DIYers.

Member benefits:

  • Get a FREE Traditional Bookcase Project Plan
  • Sign up for FREE DIY newsletters
  • Save projects to your project binder
  • Ask and answer questions in our DIY Forums
  • Share comments on DIY Projects and more!
Join Us Today
closeX

Report Abuse

Subject
Reasons for reporting post

Free OnSite Newsletter

Get timely DIY projects for your home and yard, plus a dream project for your wish list!

Follow Us