My windscreen has damage on it, will it fail an MOT?
Your car’s windscreen is a vital part of your car and it does a lot more than keep the flies off your teeth, it maintains a good vision of the road ahead.
We have all been there, smeary wipers, low sun, and dead flies all reducing your visibiliy. There are a few simple things that you can do to improve vision a lot by making sure that your windscreen is clean, inside and outside.
- Even if you’re not a smoker a hazy film will build up on the inside of the glass, in newer cars, this is worse as the plastics in the car give off a residue.
- If you have a scratches, abrasions or a chips on the outside this can makethe dazzle from the sun even worse.
- If you notice your swiper baldes are not clearing properly, then new ones are a simple and cost effective fix, many suppliers will also fit them for free of a small charge. It is worth keeping an eye on the condition of these, over time the rubber can harden and reduce the ability to wipe the screen.
- Use plenty of screen wash, in the summer use 20% wash to water, then in the winter, consider increasing this to 50%, this will help clear the salt off the screen and also reduce the risk of freezing.
Cracks or Chips
Depending on its size and position, a chip on your windscreen can be a distraction or even impair vision.
Damage of up to 40mm across can sometimes be repaired, depending on where in the screen it is situated.
- If the damage is right in front of you – in the area known as the ‘A zone’ – only damage up to 10mm (slightly less than the size of a 5 pence coin) can be repaired
- Repair involves cleaning and drying the damaged area and filling it with a clear resin with similar optical properties to glass, you will see an image below showing a repair.
- The damage won’t completely disappear but the repaired area will be much less visible and have a smooth surface
- If ignored, small chips can grow and become irreparable. Secondary cracks can form through the combined effect of heat, moisture, frost, dirt and vibration
- Any dirt or moisture getting into the chip will make it more difficult to produce a visually acceptable repair so it’s important to act quickly
The MOT test
Depending on where it’s located, some windscreen damage will result in an MOT failure if not attended to.
The screen’s divided into two areas for the MOT.
- Damage larger than 10mm across will normally result in a failure if it’s in the ‘A-zone’, a 290mm wide band centred on the steering column and bounded top and bottom by the windscreen wiper swept area
- Damage larger than 40mm across will normally result in failure anywhere else on the windscreen
Your car can fail the MOT if a wiper blade is insecure, missing, or in such a condition that it doesn’t clear the windscreen effectively to give you an adequate view of the road (through the windscreen) to the left and right sides of the vehicle, as well as to the front.
Wipers that judder, make a noise, leave bands of rain or unwashed margins should be replaced.