Your windshield washer system is simple. It’s an electric pump that delivers pressurized fluid to the nozzles at the front or rear of your car. In such a simple system, there are very few fail points.
This is why these systems seem always to work. However, if you are unlucky or drive a very old vehicle, you might have some problems with your windshield washer system.
How Does Your Windshield Washer Work?
The windshield washing system is a combination of nozzles, an electric pump, and some plumbing. This is what happens when you push your stalk to activate the washers.
- Depending on your car, a control module will activate a relay that triggers the washer pump, or the move will turn it on
- The pump draws water from the washer fluid reservoir and pumps it through a set of plumbing to the appropriate nozzles.
- Some cars use multiple pumps. One for front washers and one for the rear. Others use one pump and valves to direct the water
- The stalk switch will also trigger your wipers to run a couple of times to wipe off the fluid and clean the screen
With this simple process in mind, we can start looking at different parts of the system that could fail.
Why is My Windshield Washer Not Working?
A couple of things could go wrong. This varies depending on what car you are driving and how automated the washer system is. We will start with simple, easy-to-fix problems first.
No Fluid in the Reservoir
The first problem is no fluid in your washer reservoir. You can find it under the hood. The location varies depending on your car’s model. Consult a manual if you can’t locate it.
It has a lid with a dipstick to help you gauge the level. If it is dry, your pump has nothing to push. Check it often and top it up with windscreen washer fluid or pure, clean water.
Avoid running your washer on a dry reservoir as the pump needs this fluid for lubrication and cooling. You could quickly burn out your pump if you do it repeatedly.
You can tell if your pump is running if you hear a whirring noise if you trigger the washer, but you can’t see any fluid (even a trickle) from the washer nozzles.
Blocked Nozzles
Blocked nozzles could prevent water from shooting out and onto your windscreen. However, you will still get some weak drips and dribbles from the nozzles when you activate a wash cycle.
Also, if you are dealing with front wipers, you might have only one nozzle working.
A small pin will come in handy when clearing the nozzles. Open the hood and find the hose leading to your nozzles. There should be a way to disconnect the tube close to the nozzle.
Once disconnected, push the pin lightly into the nozzle to dislocate the dirt. For extra cleaning, you can use compressed air onto the nozzle to flush the dirt out. (Remember to keep the nozzle disconnected from the system by unplugging the plumbing. You don’t want the compressed air backing up into your pump)
While at it, you could also try running a wash cycle to see if water comes through the disconnected hose. If it doesn’t, you have more problems down the system.
Pro Tip: Clogs won’t be a problem if you use a high-quality windscreen washer fluid. If you want to cheap out and use water, stick to pure desalinated water (clean tap water should). Avoid soapy water as the soap clogs nozzles as it dries.
A Blown Fuse
If you can’t hear your pump kick on and all the above two checks are ticked off, chances are you have a faulty fuse.
Consult your user manual to get your fuse box’s schematics. Identify the washer fluid system fuse and confirm that it isn’t blown.
If it is blown, you could replace it and see if that fixes things, even if momentarily. Note that blown fuses always hint at some fault in the circuit. Check the system’s wiring and pump to ensure no short circuits – especially if the fuse is blown again immediately/after a few uses.
A Damaged Relay
Many intelligent systems use a relay to switch on the washer motor instead of a contact switch when you push the control stock.
If the relay is damaged, your motor won’t go on even if you activate it and the fuse is OK. Again, you can use your manual to check the fusebox schematics and confirm if you have a relay.
Sometimes, the relay might not be in the fusebox. If you have a car with a voice-activated or software-activated (through a touch screen) wiper cycle, it has a relay for the circuit.
A Faulty Control Module
Another possible fail point is the wipers or washer control module. Most cars don’t have a controller for this, but some do. If it fails or isn’t wired correctly, it won’t interpret instructions and take necessary action meaning that your washers won’t work.
Faulty Contacts or Wiring
Sometimes, the wiring to the pump could be faulty. You can troubleshoot it by identifying its terminals and checking if you can get 12V on the positive terminal with the washer switch on (and the car running, of cause).
If you can’t, the problems might be:
- Faulty washer switch
- A damaged relay or blown fuse
- A faulty control module
- Problematic wiring
If there is voltage, but the pump isn’t running, the problems could be
- Dirty or loose contacts. Clean the contacts to the pump and reattach them
- A faulty pump
A Damaged Pump
This is a common fault regardless of how complex your system might be. A faulty pump won’t turn on.
Since the pump is the heart of the system, you won’t get any juice even if other things are right.
Washer pumps reside in the washer bottle or next to it in the fender. You can track its location by following the washer hoses.
Listen to it for vibrations or some motion when activated. If you see none and you have crosschecked all the related circuits, chances are it is faulty.
You can bench test it to be sure. Applying the correct 12V to its terminals will jump it. If it is OK, it should run. If it doesn’t, chances are it’s damaged. Sometimes, the motor on the pump might turn, but it won’t move fluid if its impellers are damaged.
Replace the pump if necessary.
Disconnected or Leaky Plumbing
Another possible fail point is in the plumbing from the pump to the nozzles. Even though this is well protected and rarely breaks, it won’t harm a thing to check it out.
Luckily, you will get pools of water or washer fluid under the car every time you activate the wash cycle with your car parked. You can do it a couple of times when parked to confirm something is not leaking.
Check this too: Why Is My Car’s Defogger Not Working?
Another sign you have a leak (or blockage) is if your nozzles are working, but the pressure seems too low.
Bottom Line
While you might not need your windshield washer if you clean your car often, having it ready and functional could save you in emergencies. Troubleshooting it and fixing any problem soon could save your pump – assuming it isn’t the problem.