Troubleshooting Mercedes Windshield Washer Problems

Are you experiencing problems with the windshield washer on your Mercedes-Benz? This article will help you troubleshoot problems such as windshield fluid not coming out or windshield washer fluid pump not working. It is important to accurately diagnose the problem before you rush to replace the windshield washer fluid pump.

Symptoms

Windshield Washer Fluid Stopped coming out
E-Class windshield washer fluid leak
C-Class Windshield washer not working
Mercedes windshield washer hose disconnected
Washer fluid leaks on the ground
Mercedes windshield wiper fluid is not working
Mercedes washer jets are not working

The windshield washer problems fall into two main categories:

The windshield Washer Pump Does not Run
Pump Runs, but water does not spray on the windshield

Possible Issues

The fix to windshield washer fluid problems can vary depending on your issue. We have seen many cases when the problem is simply a disconnected washer fluid line which can be very easily fixed at home.

Troubleshooting Mercedes Windshield Washer Problems

To diagnose windshield washer fluid problems, you must have a digital multimeter. The Mastech MS8268 MS8261 Series Digital AC/DC Auto/Manual Range Digital Multimeter is what we use in this tutorial, but you can use any digital multimeter that you like.

1. Windshield Washer Pump Does not Run

Check Pump Operation
Turn the key to the ON position and press the windshield washer fluid switch. Do you hear the windshield pump turn on? As you perform this test, make sure to have the engine off, and key in position II or you will not be able to hear the pump turn on and off.
Check Fuses
If the pump does not work, you should check the fuses next. The fuse for the windshield fluid is on the side of the dashboard or fuse box in the engine bay. It could also be in the fuse box under the rear seat in some models. Find the fuse that belongs to the windshield washer fluid motor. Pull it out and make sure it is not burned out.
Check the power to the windshield washer pump.
Use a digital multimeter to check whether power goes to the windshield pump. You need to set your multimeter to measure DC 20-volt mode. If you need a multi-meter, consider purchasing one, there are several inexpensive digital multimeters listed on Amazon’s Best Selling Digital Multi Meter List. When you press the windshield washer switch on the steering column, you should see about 12-volt reading.
Test windshield washer pump.
If there is power at the plug, but the windshield washer pump does not work, the next step would be to test the windshield washer pump (motor). You can feel 12 volts to the pump and try running it for a few seconds.
Replace windshield washer pump.
If you conclude the washer pump is defective, you can replace it with a new one. Usually, the pumps are easy to replace. The hardest part is getting to the pump itself as, in many cases, you may need to remove body parts such as a front bumper or a fender, or the wheel lining. New replacement windshield washer pump can be purchased on Amazon. If you would rather save even more money, you can purchase a used Mercedes windshield washer pump on eBay (eBay link).

2. Pump Runs, but Water Does Not Spray on the Windshield

One very common problem that we see frequently is disconnected washer fluid lines. If the washer fluid line gets disconnected, you may experience no washer fluid spraying on your windshield or notice very little washer fluid spraying on the windshield. When this is the issue, windshield washer fluid falls on the ground. Follow the steps below to learn how we fixed a similar problem using only Multi-Purpose Cable Ties.

Inspect for leaks at the reservoir.
Inspect the windshield washer fluid lines for leaks

How to fix a leak on the Mercedes windshield washer fluid line

First, you should make sure the washer fluid pump runs when you press the windshield sprayer switch. In most cases, the pump works, but no water gets sprayed on the windscreen.
Locate the fluid leak. In our case, we had a major water leak by the hood near the nozzle area.
There are tabs that you need to release. In some cases, a few screws.
Open the hood and remove the plastic cover from under the hood.
Inspect the hoses on the windshield washer nozzle. In this case, one of them was disconnected.
Press the hose back in place and use cable ties to secure it, so it doesn’t come out in the future.
Test to make sure that water is spraying on the windshield properly.

Frequently Asked Questions

Where can I buy a replacement reservoir?
- eBay and Amazon
Where can I buy a Mercedes washer fluid reservoir cap?
- If you have lost the cap for the windshield bottle tank, you can purchase a replacement cap on Amazon.

Related Part Numbers

W163 ML320 ML 430 Windshield Washer Fluid Reservoir – 1638601160
Reservoir Tank Cap Lid MERCEDES-BENZ Wiper Washer Fluid – 9068690072
W210 E320 Windshield WASHER FLUID RESERVOIR Bottle – 210 869 12 20
W124 Washer Fluid Reservoir Tank E320 E420 E300 – 1248690720
W140 Chassis Windshield Washer Fluid Tank pumps S420 S500 – 1408600260
VDO Washer Fluid Reservoir – 246061009002D 0008692120 Mercedes MB
W211 E350 E CLASS WINDSHIELD WASHER FLUID TANK BOTTLE – 2118600060 2118600160 2118603760
W463 G500 G55 windshield washer fluid tank – 4638600060
Mercedes GLK Washer Reservoir Tank Windshield Fluid – 2048690320 204 869 03 20
W221 S550 S-Class – 2218600160
W215 W220 S500 S600 S430 CL500 CL600 S65 Washer Fluid Reservoir Windshield – 2208690020 / 220 869 00 20 / 89533025001 / 895 33025 001 / 220-869-00-20
R230 2003-2006 Mercedes Benz SL500 SL55 SL600 Convertible Windshield Washer Fluid Tank -A2308690020 2308690020 230 869 00 20
R170 01-04 MERCEDES SLK320 WINDSHIELD WASHER FLUID RESERVOIR – R170
W203 MB C230 C240 C280 C32 AMG CLK320 CLK500 CLK55 Windshield Washer Fluid Reservoir – 2038690020 203 860 01 60 2038600160 2001 2002 2003 2004 2005 01 02 03 04 05
W208 99-03 MERCEDES CLK430 CLK320 WINDSHIELD WASHER FLUID RESERVOIR TANK – 208 869 00 20 2088690020