How to Diagnose Your Cars Non-Functioning Windshield Wiper Motor

Hi. I'm Mike from 1AAuto. We've been selling auto parts for over 30 years!

In this video, we're going to show you how to diagnose a windshield wiper motor. If you need parts for your vehicle, click the link in the description and head on over to 1AAuto.com.

All right, we're going to test the circuit for the wiper motor. The first thing you want to do is make sure your test light works. I'm going to hook this to ground and test it. As you can see, the light's coming on. You can get this test light at 1AAuto.com, so we're good there.

We're going to disconnect the connector. Remember, keep your hands clear of any mechanical moving parts. Disconnect that. Okay, so here's your electrical connector. We're going to test it with the test light. We have our test light on ground.

This yellow wire is a hot feed that feeds the motor all the time when the key is on. We're going to test that. Lightly touch on the terminal and as you can see, the light is coming on. That is what's going to bring the motor back to park when you shut the wipers off.

The next thing we're going to test is this red and blue wire. Right now, it's not on because we don't have our switch on, so we're going to turn the switch on. We'll put that to wipers on, regular speed and as you can see, we have power there, so that means the switch appears to be working.

I'm going to put it on high now. With the wipers on high, that is not on. This black and blue is the wipers high. As you can see, the light is coming on when I test that.

Now turn the switch off again. With the wiper switch off, now I'm going to disconnect the test light from the negative post on the battery. I'm going to switch to the positive post. I'm going to test it again to make sure that I have a good connection there.

Now, I'm going to test the ground circuit for the wiper on. That is the black wire on this connector. We'll lightly test that. As you can see, the light is working. So now, we know our ground wire is good. The ground is good and all the powers are good.

If you have a problem with your wiper motor and all this tests out, you have a bad wiper motor. If you tested all these circuits and one of them is not working properly, you may have a bad wiring, a bad wiper switch, or a blown fuse.

Thanks for watching. Visit us at 1AAuto.com for quality auto parts, fast and free shipping, and the best customer service in the industry.