Windshield wipers are perhaps one of the most important vehicle components that are at the same time completely underrated by most drivers. But just take a minute to think of what it would be like to drive without them during heavy rain or snow.
Yeah, it’s an absolute nightmare, right?
That explains why windshield wiper problems make up a big proportion of the mails we receive. Because this is a problem that we know affects a lot of CarAutance readers, we’ve put together this article. We’re going to take a look at 5 of the most common reasons that can affect the operation of your windshield wipers.
You can skip this section if you like, but we thought it was cool! So it turns out that a woman from Alabama called Mary Anderson invented the windshield wiper way back in 1903.
So yeah, can you really believe that… something was invented in Alabama!
Whilst travelling in a winter storm, Mary observed that the driver of the vehicle had to dismount every few yards to manually clear snow and sleet from the windshield. To combat this, she designed a wiper device that, operated via a series of levers and pulleys, could clear the windshield from inside the car.
It wasn’t until 1923 that electric motors were added to the design. This produced the “Intermittent” (or Automatic) windshield wiper that we see today. We can thank
American engineer Raymond Anderson for this innovation, meaning that the US has played a huge role in the design and development of the windshield wiper.
Moon landings, atom bombs, microwave popcorn and windshield wipers… you’re welcome, world.
So now you have an idea where your wipers come from, but that isn’t a huge comfort if the problem is that they aren’t working properly! Luckily, the windshield wiper system is one of the more straightforward and simple systems on a car.
That means there are only really a few things that can go wrong with it. That makes diagnosing – and fixing – the problem well within the remit of most at home mechanics.
Here then are five of the most common causes of defective windshield wipers.
Environmental Factors Affecting the Blades
The first factor to check for is environmental factors that could be affecting the operation of the blades. By this we mean things in the operating environment of the windshield wipers that could be blocking their movement.
All this really means is has anything got stuck in or around the blades or wiper mechanism that could be stopping it working? This problem is going to be particularly prevalent during winter or fall.
The issues in winter are pretty obvious. Check for heavy snowfall that could be lying on the wipers. The wiper motor is not particularly strong, and it will struggle to simply move the blades if they are weighted down with lots of snow.
You should also check that the wiper blades have not simply frozen to the windshield glass. If they have, DO NOT pour boiling water onto them, as it can shatter the windshield glass. This, we shouldn’t need to tell you, is bad news.
Leaves are your enemy in fall. They probably aren’t heavy enough to stop the windshield wiper blades in themselves. But they can gum up the moving parts of the wiper mechanism, especially if they are wet or have been left to rot for a while. Carefully brush away and clean leaf debris out of the mechanism and it should be fine.
That’s about it as far as environmental factors, unless a family of raccoons has set up a home on your windshield. If the wiper system looks clear of obstructions and is still not working properly, then you probably have a mechanical fault, sir.
Loose Pivot Nuts
Whilst loose pivot nuts may sound like a medical condition that affects male strippers, it is actually one of the most common mechanical failures that can affect your windshield wipers. The blades that actually do the windshield wiping are attached to arms that in turn are connected to the windshield wiper transmission via pivot nuts.
The transmission itself is attached to the windshield wiper motor, and it works to transfer the force generated by the motor into a sideways movement of the wiper blades across the windshield glass. The pivot nut, by connecting the arm to the transmission, is therefore a very important but often overlooked part of the whole system.
If the nut is loose, you may see the arm move very slightly when you activate the wipers. We’re talking more like the twitching arm of a zombie than the strong sweeping action of a fully working system. Each arm has it’s own pivot nut too, to you may see one arm fail to move whilst the other carries on working.
If you see either symptom take a look at the pivot nuts. They do need to be really tight, so if there is any play in them at all, simply take a small spanner or similar tool and re-tighten the nut.
Burnt out Wiper Fuse
The power to move the windshield wipers is generated from small windshield wiper motors. These electrical motors are installed in the car in the form of a simple and complete electrical circuit. As you will find in just about any electrical circuit, the windshield wiper motors are equipped with fuses.
Fuses are of course deliberate weak points in electrical circuits, designed to protect motors (for example) from damage by overload. In the case of the windshield wiper circuit, the fuse is there to protect the motor from burning out from overload stress caused in the operation of the motor.
What does that mean in reality? Look back up the article to problem number one. If the wiper blades are obstructed, say by snow or ice, and you haven’t noticed this then turning on the wipers will overload the motor. That is because it will struggle to operate the blades even as they refuse to move.
That is why it’s important to always check for obstructions before firing up the windshield wipers, especially during winter and fall. If your windshield wipers worked fine today, got stuck on ice this morning and now refuse to work even with the obstruction cleared away then you have likely blown a fuse.
Replace the fuse in the motor as soon as you can, and that should cure the issue. If it doesn’t, you may have fallen to the most serious – and annoying – windshield wiper fault of them all.
Dead Wiper Motor
If the fuse fails to do its job properly, the windshield wiper motor can still burn out before the fuse does. Aside from this reason, the windshield wiper motor can fail often for no particular reason at all. At the end of the day it is a relatively simple little motor, and sometimes it can be accidently built with a faulty part inside or sometimes not installed properly during the manufacture of the car itself.
If you’ve ever owned any device with an electrical motor – from a lawnmower to a little RC car – you will know sometimes electrical motors break down. Is there anything you can do about this? The short answer is no, not really.
So if your windshield wiper blades are not moving, and you have been through all the symptoms above then the most likely cause is that the motor has simply died and gone off to motor heaven. You could try to repair it, but a new one will only set you back a few bucks and an hour or two of work to remove and replace.
Since the wipers won’t work without the motor in place though, we would suggest that you replace the dead motor as soon as possible.
That then represents the three main mechanical failures that can stop your windshield wipers working properly, and even stop them working completely. If you’ve ruled out mechanical failure, then the next thing to do is to check the blades themselves.
Damaged Blades / Arms
For a device that is designed to be mounted and spend its entire operating life on the outside of a speeding car, the windshield wiper blades are surprisingly fragile. In part this is a necessity. The stronger the wiper blades and mechanism, the heavier it would be. The heavier it is the larger the motor needs to be. So in sense the wiper blade mechanism is kept light to keep the load on the motor low.
That though does mean they can be susceptible to damage during driving and often just when the car is sat parked up. Luckily this is about the easiest form of damage to detect and repair. All it really needs is a quick visual inspection, and if you spot any damage to the arm or wiper blade, replace with a new part.
It’s a simple but effective piece of vehicle maintenance.