Can I repair the rear wiper myself on my Toyota Yaris?

Question

I have a 2nd-generation Toyota Yaris. Recently my rear wiper stopped working; it doesn't move when I turn it on.

If I turn the wiper "on", then get out the car and walk around to the back, I can clearly hear a whirring/humming sound coming from the base of the wiper, which suggests that the wiper's motor is still working and turning. I can't see any obvious obstruction or blockage that might be getting in the way of the wiper itself.

Is there a realistic chance that I can fix the wiper myself? I'd rather save the money if possible. What are the likely causes of the problem? How would I go about diagnosing exactly what's wrong, and figuring out how to fix it?

Answer 1

Easiest fix would probably be to buy a complete wiper assembly from a vehicle breakers yard (or Ebay) and swap your old one for the new. It should be simple enough for a noob to do.

From your description, it is likely that the plastic gears inside have been stripped of teeth. Have you tried moving the arm while the motor is humming its tune? You may find the arm starts to move itself if some good teeth mesh.

Answer 2

The symptoms you describe would indicate that the electrical portion of your rear wiper system is working. It's likely there is an internal failure of a mechanical component of the wiper motor.

Consider to check out various sources of this motor assembly. Ensure that you are getting the entire assembly, including the gearbox, as you have reason to believe (whirring sound) that the motor is running. Examine the photos of the sources you discover to note bolt placement and wiring, which would also have a connector on the wiring.

The trickiest part, in my experience and opinion, is going to be removing the body panels from inside the vehicle. It's not tricky, it's only the trickiest part. Sometimes the plastic rivets used to hold the panels in place will break before they release, which then requires to purchase new ones.

You can consider also to purchase an inexpensive (harbor freight?) panel release lever set to assist the process.

Once the panel is removed, you should be able to see the fasteners for the wiper motor, as well as the matching connectors.

Prior to all this, also consider to examine the fastener of the wiper shaft to the vehicle. It may be a threaded collar that slides off after you remove the wiper arm. This is the last point of removal, as you want the collar to hold everything steady while you are working in the panel area.

Answer 3

First, let me congratulate you on your desire to repair things on your own.

Like most problems we try to solve this by dividing the problem:

1. You need to figure out how to remove and reinstall the motor.
2. You need to figure out how to repair the item.

While I have no experiences with Toyotas and cannot judge your abilities, I suppose that task #1 should be doable with basic tools and some mechanical understanding.

Task #2 should be more challenging, especially as spare parts for the motor ought to be difficult to get. I would suggest you to skip #2 and get a spare motor and install this one. Buy also a matching new wiper arm as apparently those are difficult to remove without damage, perhaps you can give it back in case you won't need it. Try to use second source items (online part dealers are your friend here) as the original ones are costly. Evade the used ones as the treading is often damaged, complicating your work.

The best tip I can give:

Plan you work so you have enough time, especially that you won't get in a hurry if you desperately need a car while waiting for some parts/tools. Most errors I made happened because I got stressed or distracted.

Suggested tools:

• Wrench set
• Pliers
• Screwdrivers
• Perhaps some Torx-bits / drivers
• Eventually a small two-arm puller
• Plastic lever wedges

Suggested steps (just doing this from theory as I never did this on the rear wiper):

1. Loose the nut holding the arm.
2. Remove the arm with the puller, place the spindle of the puller on the loosened nut. If you do not have a puller: Place a matching fork wrench under the arm, around the spindle. Use some pliers to force the arm out. (https://youtu.be/02oYFR9KZ4Q)
3. Gently remove the inside paneling and the moisture barrier foil without damaging it.
4. Unclip the electrical connector.
5. Unbolt the wiper motor.

On reinstalling, pay attention to attach the wiper arm on the correct position..