Your headlights are a vital safety feature, without your lights you wouldn’t be able to see where you are going, and other road users wouldn’t be able to see you either, so it’s vital that they are in the best possible condition at all times.
Headlights are often affected by the harsh weather conditions such as driving in heavy rain, fog and sleet. They can also be covered in spray from cars in front of you or splashed by passing motorists. As a result they can start to take on water, especially if your car is an older model and the seals around the lights are starting to wear thin.
If water builds up inside your headlight cover then it can reduce the effect of your lights. The water can move around inside the cover, preventing the light from shining through clearly, and it can also settle inside the cover and start to create mould – again reducing the effect of the lights.
If you find yourself in this position, read on for the step-by-step solution to manage headlight condensation.
Step 1: Take the headlight out completely
To start with, remove the headlight completely. This is either done by accessing the bulb from under the bonnet or by removing the glass cover on the outside of the vehicle.
When you remove the headlight bulb make sure that you are very careful as the traditional bulbs are very easily damaged. It is best to wear a pair of protective gloves just in case the glass breaks, and you should ensure the bulbs aren’t hot either, so give your car time to cool down if you have just driven it.
In addition to removing the bulb, you also need to remove the connector. This is the part that transmits the electrical supply from your car’s battery to the bulb itself.
If you are putting the same bulb back into the car, be sure to put it somewhere safe and out of the way so that you don’t damage it before putting it back in place. However, this may be a good time to upgrade or replace your existing bulbs.
Step 2: Fill the headlights with water
Yes, you read that right. You will have to remove the headlight cover and fill it with water so that you can locate the leak where the water is getting in.
To remove the headlight cover you will need a small screwdriver, and it will need extreme care to avoid dropping and breaking the glass any more than it already has been.
Having removed the headlight cover, take it to a bucket of water (or a sink), and fill the light with water. If there is any damage to the headlight itself you will see the water escaping through the affected area.
Step 3: Empty all of the water and dry your headlights
Having located the damage, mark it using either a marker pen or masking tape if you can fix it, and allow the headlight to dry fully before you attempt to make your repair. If the crack is too large to repair then it may be worth investing in completely new headlights.
Step 4: Seal the headlights
If the headlights are salvageable then you can use a range of plastic or glass sealants (depending on the material of your headlight or the cover, and the location of the crack) to stop the water from penetrating again.
Should the crack appear in the centre of the headlight rather than along the joint then the sealant may reduce the effectiveness of the light so you will have to change the whole headlight.
For more advice for driving in the rain, read our guide here, or visit the blog for more articles on car maintenance and driving tips.