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What are the common problems with the keyless entry system in a 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What are the common problems with the keyless entry system in a 2021 Toyota Highlander?

What are the common problems with the keyless entry system in a 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
709 words

Problem Statement

Discover common issues with the keyless entry system in the 2021 Toyota Highlander, including symptoms, diagnostic steps, and repair instructions.

Affected Component
keyless entry system

Symptoms

  • •Key fob not unlocking/locking doors.
  • •Range of key fob operation is reduced.
  • •Warning light on the dashboard indicating key fob battery needs replacement.
  • •Key fob works intermittently or not at all in certain locations.
  • •Other electronic devices may be malfunctioning when near the vehicle.
  • •Key fob does not respond despite having a new battery.
  • •No LED light activation when buttons are pressed.
  • •Doors lock/unlock randomly without user input.
  • •Doors do not respond to key fob commands.
  • •Physical locking/unlocking via door handle is ineffective.

Diagnostic Steps

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Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •Multimeter
  • •Small screwdriver
  • •Replacement battery (typically CR2032 for Toyota key fobs)
  • •OBD-II scanner
  • •Spare key fob (if available)
  • •Digital multimeter
  • •Wiring diagram (from service manual)
  • •Screwdrivers
  • •Replacement door lock actuator

Additional Information

Affected Component
keyless entry system
Difficulty
medium
Severity
medium
Tools Required
9 items

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Common Problems with the Keyless Entry System in a 2021 Toyota Highlander

Keyless entry systems provide convenience, but they can encounter issues. Below are common problems along with symptoms, diagnostic steps, tools required, and repair instructions.

Common Problems
  1. Key Fob Battery Failure
  2. Interference from Other Electronic Devices
  3. Faulty Key Fob
  4. Malfunctioning Keyless Entry Module
  5. Door Lock Actuator Failure
Problem 1: Key Fob Battery Failure
Tools Required
  • Multimeter
  • Small screwdriver (for opening the key fob case)
  • Replacement battery (typically CR2032 for Toyota key fobs)
Repair Instructions
  1. Open the Key Fob: Use a small screwdriver to carefully pry open the key fob.
  2. Replace the Battery: Remove the old battery, noting its orientation, and insert the new battery.
  3. Reassemble the Key Fob: Snap the fob back together and test it.
Problem 2: Interference from Other Electronic Devices
Tools Required
  • None specifically, but a note pad for observations may be useful.
Repair Instructions
  • If interference is confirmed, avoid using the key fob near suspected devices. If problem persists, consider seeking a professional for further diagnosis.
Problem 3: Faulty Key Fob
Tools Required
  • OBD-II scanner
  • Spare key fob (if available)
Repair Instructions
  • If the key fob is faulty, you may need to program a new key fob at a Toyota dealership or with a professional locksmith.
Problem 4: Malfunctioning Keyless Entry Module
Tools Required
  • OBD-II scanner
  • Digital multimeter
  • Wiring diagram (from service manual)
Repair Instructions
  1. Locate the Keyless Entry Module: Refer to the vehicle’s service manual for location.
  2. Inspect and Repair Wiring: Repair any damaged wires or connectors.
  3. Replace Module if Necessary: If module is faulty, disconnect the battery, replace the module, and reconnect.
Problem 5: Door Lock Actuator Failure
Tools Required
  • Multimeter
  • Screwdrivers
  • Replacement door lock actuator
Repair Instructions
  1. Remove Door Panel: Carefully remove the door panel to access the actuator.
  2. Disconnect Actuator: Disconnect the wiring harness from the actuator.
  3. Replace Actuator: Remove and replace the faulty actuator with a new one.
  4. Reassemble Door Panel: Reinstall the door panel and test the keyless entry system.
Conclusion

If you encounter issues with the keyless entry system in your 2021 Toyota Highlander, following these steps can help diagnose and repair common problems. If the issue persists after troubleshooting, it may be beneficial to consult with a certified Toyota technician for further assistance.