Simple Wiper Relay fix

Hi Guys, Thought Id share a quick repair I did today on my 2000 328Ci. Its been raining heavily and my wipers have been working overtime when I discovered this issue.

Symptoms : Wipers just stop working for no apparent reason, then suddenly start working for no reason! When it does work, the blades move normally without hesitation.

Well after ruling out all the other causes, mine turned out to be a faulty Wiper Relay. Part#61368384505.

Since my closest dealer didnt have stock of the relay, and I had to shell out $47CAD for it anyways. I decided to try repairing the relay. I dont expect every relay to be repairable, but this simple fix should fix most. I know this is not a big $ repair, but I like fixing stuff.

Disclaimer!!! I dont take responsibility if you screw up your car, yourself or anyone around you as a result of this diy. This is purely for information about something I did to my car. If you are unsure about anything, take your car to a professional.

Always a good idea to disconnect your Negative terminal on your battery before stuff like this.

First locate the ECU/Relay box in the engine bay on the Driver Side, loosen the 4 screws, remove the cover


The Wiper relay is light Brown or Tan colored cube


Once you get the relay out, there are two tabs on the bottom that you can pry the relay out of its casing.




Now you got the relay out of its casing, you can examine its contents.


The main area of interest (and main failure spot) is the bottom relay closest to the pins. This relay is what turns on/off the wipers. Especially on older vehicles, and wet climates where wipers are used often, Oxidation builds up between the contact due to the constant spark between these points. It builds up so much that it blocks the signal and your wipers dont work. All I did was clean the contacts with a bit of sandpaper to remove the oxidation.


Get some sandpaper in there to brush the oxidation off the contacts


Voila! pop the cover back on the relay, reinstall, and your intermittent wiper problem should be solved. Mine work as good as new, and its been raining heavily!

Just done the same on mine as I was experiencing same issue. Good write up mate,
Hope I'll get away with getting a new one, alltough I've heard they only bout £20 anyway.

Thanks for the write up. my wipers just died.. almost like I just turned the switch off in a middle of driving at 55mph in heavy rain (FUN!). Since there was no stutter or slowdown of a motor dying, I didn't think it was a drive motor or anything like that, but more of an electrical connection or switch problem.

I'm did this fix (although instead of trying to clean the contact, I just replaced the relay)... and now I have a fully working wiper! saved me a bundle taking it to a mechanic. thanks!!!

You just saved my life. Thank you so much... Worked like a charm!

This was a great post. Very helpful. Had this intermittent wiper failure for several months now. Caused several dangerous situations at high speed in rain. Used your post to help replace my relay. My old unit was not corroded like yours, so I hope it was the problem . . . Thanks again for the post.

....is to use a relay contact file to clean the contacts.