Headlight Adjustment Guide

Modern Car Headlight

Most modern cars will come with a very simple way of adjusting the level of the headlights – usually by way of a switch on the dashboard. This switch will usually have a scale of 1-3 or 1-5, allowing the driver to set their preferred level of headlight beam very easily. Some vehicles now even have an automatic levelling system, meaning the car adjusts the height of beam as it detects any changes to the vehicle.

The difference in heights is there so you can adjust the level of the beam according to the situation or conditions, for example when towing a trailer or caravan or just having a heavy load in the boot. As there will be more weight on the rear of the vehicle, the front will ride up slightly and this will mean the headlight level should be adjusted downwards to compensate for this change. This will ensure the lights do not dazzle other road users and visibility is still at an optimum level.

The vehicle’s handbook will have a section regarding the headlight height adjustment so it will be worth finding this and reading carefully, especially if you plan to tow anything behind the vehicle. The height adjustment will be set within legal limits but it is up to the driver to set the best level according to the situation or road conditions.

For those who have a vehicle without electric or automatic height adjustment, you may need to adjust your lights manually. This is usually very simple, as most headlights will have a screw or allen key slot so you can adjust the beam by hand.

Light Level Check

The height of the headlight beams are a crucial part of the MOT process, so maintaining the headlights and height adjustment is very important. It’s a good idea to check the lights regularly and spot any issues – such as condensation building up inside the lens or any cracks or damage in the outer lens. These issues could prevent the lights from functioning correctly and may lead to a MOT failure. You can check the level of the beam at home if you can position the vehicle against a wall or garage door and measuring the height of the beam.

To check your headlights are adjusted correctly, it is generally advised to park on a level surface, 10 feet from a wall or garage door. Measure the height from the floor to the centre of your headlight, and check the beams appear on the wall at the same height. If you have more weight in the rear of the car, the beam will be high, and will need adjusting downwards.

If you are looking at travelling abroad, you may need to consider using a set of beam deflectors. These simple add-ons will prevent your vehicle’s lights from dazzling road users when the car is being driven on the opposite side of the road. The deflectors must then be removed again before driving on UK roads.