Why Are My Headlights So Dim?

Headlights give us the freedom to safely drive whenever we’d like no matter the weather conditions or time of day, but when they’re experiencing issues, you could be left driving in the dark. Dim headlights aren’t just an inconvenience, they are a safety hazard. Not only will you have trouble seeing, other drivers will have trouble seeing you! What could be causing dim headlights in your vehicle, and what should you do next?

LED headlight of blue BMW

Five Possible Causes of Dim Headlights

If you’re experiencing dim headlights, here are five common causes that may be the reason.

Foggy Lenses

One of the simplest explanations for your headlight’s reduced light output is a problem with the lens itself. Modern headlight lenses are made of clear acrylic, rather than the glass lenses used on classic vehicles. While this material is inexpensive and durable, it also undergoes oxidation from UV light exposure. This process will turn the once-clear acrylic foggy, cloudy, and/or yellow. 

The best fix for this (beyond headlight replacements) is to have your headlight lenses restored. With the proper experience and equipment, your lenses can be refinished by a professional back to their factory-level clarity.

Burnt-Out Bulb

The most obvious and most common reason for headlight issues is dead or dying bulbs. Similar to the lightbulbs in your lamps at home, automotive headlight bulbs can also burn out over time. The fix is luckily just as simple as the issue though, as headlight bulb replacements will return your lights to the proper brightness.

Failing Alternator

Sometimes, headlight issues aren’t related to the headlights themselves. If your vehicle has an alternator that’s not generating the proper amount of electricity to power your headlights fully, you may notice your lights are flickering or dim. 

Alternator in  engine bay

If you notice your lights are bright on initial startup (when running on battery power) and later become dim when switched over to alternator power, you likely have an issue with your alternator. 

Wiring Issues

The headlights in your vehicle are powered and controlled by various wires, each with a crucial purpose. When one of these wires is damaged or corroded, it can prevent your headlights from working as they should. While bad wires are a rare cause of this issue, it’s not unheard of and can be one of the most difficult problems to diagnose. 

Moisture Buildup

If you notice water droplets or fog on the inside of your headlight lens, this may prevent your lights from shining as bright as they should. Moisture buildup occurs when your headlight housing or seals have damage that allows water to enter the inside.

This should be taken care of promptly, as moisture can cause further damage to sensitive electronic components in your headlight if left unaddressed.  

Headlight & Accessory Repair at Toledo Tire & Auto Care

If you’re experiencing issues with your headlights or other accessories, trust the experts at Toledo Tire & Auto Care for your inspection, diagnosis, and repairs! Our ASE Certified technicians have years of experience working on all makes and models. Give us a call or schedule online with us today!