What should I do if the windshield wipers stop working on my 2020 Toyota Highlander?

If the windshield wipers on your 2020 Toyota Highlander have stopped working, it can be due to several reasons including a blown fuse, a faulty wiper motor, or issues with the wiper switch. Below is a detailed troubleshooting guide to diagnose and potentially fix the issue.

Tools Required

• Multimeter
• Fuse puller or needle-nose pliers
• Screwdrivers (flathead and Phillips)
• Ratchet and socket set
• Replacement fuses (if necessary)
• Electrical contact cleaner (optional)
• Service manual for wiring diagrams (optional)

Step 1: Check the Wiper Switch

1. Verify Operation:

   • Ensure the ignition is in the "ON" position.
   • Turn the wiper switch to different settings (low, high, intermittent) and observe for any response.

2. Test the Wiper Switch:

   • Disconnect the wiper switch connector.
   • Use a multimeter to check for continuity in the switch terminals while toggling the switch. Refer to the service manual for the specific pin configuration.

Step 2: Inspect the Fuses

1. Locate the Fuse Box:

   • Open the driver's side door and locate the fuse box. It may be located under the dashboard on the driver's side or in the engine bay.

2. Check the Wiper Fuse:

   • Using the fuse puller or needle-nose pliers, remove the wiper fuse. Refer to the fuse diagram on the cover of the fuse box or in the owner’s manual.
   • Inspect the fuse for any visible signs of damage (burnt or broken filament).
   • If the fuse is blown, replace it with a fuse of the same amperage.

Step 3: Test the Wiper Motor

1. Access the Wiper Motor:

   • Remove the wiper arms using a flathead screwdriver or a puller if necessary.
   • Remove the plastic cover (cowl) under the windshield to expose the wiper motor.

2. Check Power to the Motor:

   • Disconnect the wiper motor's electrical connector.
   • Set your multimeter to the voltage setting and connect the leads to the motor connector terminals.
   • Activate the wiper switch and check for voltage (around 12V). If there is power, the motor may be faulty.

3. Test the Ground:

   • Verify that the ground connection for the wiper motor is secure and free of corrosion. A poor ground can prevent the motor from operating.

Step 4: Inspect Wiring and Connections

1. Check Wiring:
   • Inspect the wiring harness leading to the wiper motor for any visible signs of wear, fraying, or damage.
   • Look for loose or corroded connections that could disrupt electrical flow.

Step 5: Replace the Wiper Motor (if necessary)

1. Remove the Old Motor:

   • If the wiper motor is confirmed faulty, disconnect the wiring harness and remove the mounting bolts using a ratchet and socket.
   • Carefully remove the motor from the vehicle.

2. Install the New Motor:

   • Position the new wiper motor in place and secure it with the mounting bolts.
   • Reconnect the wiring harness to the new motor.

3. Reassemble:

   • Reinstall the cowl cover and wiper arms.
   • Make sure everything is secured properly.

Final Steps

1. Test the Wipers:

   • Turn on the ignition and test the wipers to ensure they are functioning correctly.

2. Check for Additional Issues:

   • If the wipers still do not work, consider further diagnosis or consult a professional technician, as there may be more complex electronic issues involved.

Conclusion

By following these steps, you should be able to diagnose and potentially fix the issue with the windshield wipers on your 2020 Toyota Highlander. If after all these steps the problem persists, it may require professional assistance or further electrical system diagnostics.