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How to Diagnose Wiper Transmission Motor 04-09 Subaru Outback

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  1. step : Removing the Wiper Arms (0:27)
    • Mark the position of the wiper blades on the windshield with a dry erase marker
    • Open the hood
    • Pry the cover off the wiper arm studs with a pick tool
    • Remove the 14mm nut from each wiper arm stud
    • Pull the wiper arms off the studs
  2. step : Removing the Wiper Cowl (2:20)
    • Remove the three push clips from each cowl bracket using a trim tool
    • Pop the cowl clips out of the frame with a trim tool
    • Pry the bracket off each side of the cowl with a trim tool
    • Pull the cowl off from under the hood
  3. step : Testing the Wiper Switch (4:34)
    • Turn your key to the on position
    • Connect the test light ground to the negative battery terminal
    • Touch the test light probe to the positive battery terminal
    • Check that the test light lights up to ensure the test light works
    • Disconnect the wiper motor electrical connector
    • Touch the test light probe to the terminal for the park (yellow) wire on the wiper motor electrical connector
    • Check that the test light comes on
    • Turn on the wiper function, using the stalk
    • Touch the test light probe to the terminal for the run (red and blue) wire
    • Check that the test light comes on
    • Put the wiper on high with the stalk
    • Touch the test light probe to the terminal for the high (black and blue) wire
    • Check that the test light comes on
    • Turn the wiper switch off
    • If all functions light the probe, the switch is working
    • If any function does not light the probe, this could indicate a switch, wiring, or fuse problem
  4. step : Testing the Ground (6:37)
    • Disconnect the test light ground from the negative battery terminal
    • Connect the ground to the positive battery terminal
    • Touch the probe to the ground (black) wire on the wiper motor electrical connector
    • Check that the test light comes on
    • If all functions worked in Step 3 and the ground works, then the wiper motor is the problem
  5. step : Installing the Wiper Cowl (7:37)
    • Connect the wiper motor electrical connector
    • Push any clips disconnected from the cowl back into the cowl
    • Line up the cowl on the frame
    • Push in the cowl clips
    • Slide each cowl bracket under the fender
    • Clip the cowl brackets onto the cowl
    • Push the three push pins into each cowl bracket
    • Clip the weatherstrip to the cowl
  6. step : Installing the Wiper Arms (10:36)
    • Line up each wiper arm with the windshield mark from Step 1
    • Slide the wiper arms onto their studs
    • Fasten the 14mm nuts onto the wiper arm studs
    • Torque the 14mm nuts to 14 foot-pounds
    • Clip the covers onto each wiper stud
  7. step : Testing the Wipers (12:15)
    • Close the hood
    • Turn the key to the on position
    • Test the wipers with the stalk on all settings
    • Check that the wiper path is correct
    • Turn the wipers off to test the park function

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

In this video, we are going to show you how to diagnose your wiper motor in a 2008 Subaru Outback. If you need parts for your vehicle, click the link in the description and head over to

Before we take the wiper arms off, we're going to want to mark where the old blades are. You can use a dry-eraser marker, or a piece of chalk, or a crayon would work, just something you can mark and then wipe off. I'll do the same with this one. Just put a little mark there, so, when you put it back, you know that's where the blades should be on the windshield.

I'm going to pull this cover off, right here. I'm going to use a 90 pick, and pry up, underneath. It'll release. I'll do the same for this one. You can use a flat-blade screwdriver as well. Pull those covers off.

I'm going to take this nut off. I'm going to use a 14 millimeter socket, an extension, and a ratchet. Break it free, and then you can use just the socket and the extension. Pull that nut out. To pull this arm up, I'm just going to wiggle it back and forth, push down, and pull up, and the whole arm should come out. Now, I'm going to take this one off with the same 14 millimeter socket, an extension, and a ratchet. Break it free, and then twist it off. Pull the arm up, and do the same. Grab it, and push, and pull. There's the wiper arm.

Next, we're going to take these push clips up. There's one right there. There's these three right there. For this one, right here, we're going to use a trim tool. We sell these at I'm just going to pry it underneath the panel, pry up, just to pop that out. For these little ones, I'm going to use a right-angle pick, just to get it underneath. You release the top part, and the rest of it pulls up. We're doing the same for the other side. Lift that up.

Next, we're going to take our trim tool and come under here, and we're going to pop this up. There's some clips that hold it on. Underneath, just like this. There's a clip under here. I'm going to pull that up and out of the way. Same with this side. There's a clip that pops this up, and then this slides out from under the fender. I'm going to pull the cowl cover off.

All right, we're going to test the circuit for the wiper motor. First thing you want to do, make sure your test light works. I'm going to hook this to ground, and test it. As you can see, the lights coming on. You can get this test light at We're good there, so we're going to disconnect the connector. Remember, keep your hands clear of any mechanical moving parts. Disconnect that, okay.

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. Just lightly touch on the terminal. 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. We're going to turn the switch on. We'll put that to wipers-on, regular speed. As you can see, we have power there. 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, we'll turn the switch off again.

With the wiper switch off, now I'm going to disconnect the test light from the negative posts on the battery. I'm going to switch it to the positive posts. I'm just going to test it again and make sure that I have a good connection there. Now, I'm going to test the ground circuit for this wiper arm. That is the black wire on this connector. Just lightly test that. As you can see, the light is working. 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 bad wiring, a bad wiper switch, or a blown fuse.

Next, we're going to connect our electrical connector. Remember to keep clear of the mechanical mechanism, because you don't want to hurt your fingers. It's going to go in with the skinny side to the top, the clip on the bottom, just like that.

Push our push clip back in there. It holds the wire there. Some of these clips may have fell off. You're going to reinstall these clips on the cowl, up here. Twist this around, and go over. You're going to want to go over the wiper transmission, line all this stuff up, start pushing it down. Line this up and push this push pin down there. Do the same on this side. Line this up and push this push pin down here.

We can take these. I'm going to insert them over here. Go under the fender first, and push that down. Do the same on this side. Go under the fender, push that down. Next, we're going to install these push pins. You want this top part to be up a little bit. Install the bottom part, and then you can push it down, just like that. Same with this one.

Sometimes, you can push the lower part of the clip in first, and then push the upper part in like that. Install them on this side as well. Push it down. Now, we're going to push these in, that are on the weather strip. Get these locked down in.

Next, we're going to install our wiper arm. Put that on. We're going to line it up with our marks that we made earlier, right there, install our nut for the wiper arm. This is our 14 millimeter socket and extension. Tighten this down. We're going to torque these to 14 foot-pounds. We'll take this one. We're going to install this one over here. Make sure that lines up with our marks over there. Snug this down with the ratchet, and then we'll torque it to 14 foot-pounds. I'm going to hold the arm while I'm torquing it.

You can put the covers back on. I'm going to slide this down into the groove, press it down. Same with this one. Slide it in abd push it down. Now, we'll close the hood. I'll turn the key on and test them. We want to make sure that it's not coming off the edge of the windshield, and that they're not hitting each other. We'll test them on high. It works on high. It goes back to park.

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

Tools needed for replacement:

    Diagnostic Tools

  • Test Light

  • General Tools

  • Pick

  • Materials, Fluids, and Supplies

  • Marker / Writing Utensil

  • Ratchets & Related

  • Socket Extensions
  • Torque Wrench
  • Ratchet

  • Sockets - Metric

  • 14mm Socket

  • Specialty Tools

  • Trim Tool Set

Voltage Circuit Test Light

Test Light Performance Tool W2975C

Part Details

  • Lead Length: 42 in. Lead Wire
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