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How do I resolve issues with the keyless entry system in my 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How do I resolve issues with the keyless entry system in my 2021 Toyota Highlander?

How do I resolve issues with the keyless entry system in my 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
1-2 hours
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
602 words

Problem Statement

Learn how to diagnose and fix keyless entry issues in your 2021 Toyota Highlander with our step-by-step guide.

Affected Component
keyless entry system
Estimated Time
1-2 hours

Symptoms

  • •Key fob not responding to unlock/lock buttons.
  • •Key fob not detected by the vehicle when inside.
  • •Vehicle not responding to keyless entry (e.g., door handles not unlocking).

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4

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

  • •Small flathead screwdriver or coin
  • •new CR2032 battery
  • •OBD-II scanner
  • •basic hand tools
  • •multimeter

Additional Information

Affected Component
keyless entry system
Estimated Time
1-2 hours
Difficulty
medium
Severity
medium
Tools Required
5 items

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Resolution for Keyless Entry System Issues in a 2021 Toyota Highlander

Symptoms:

  1. Key fob not responding to unlock/lock buttons.
  2. Key fob not detected by the vehicle when inside.
  3. Vehicle not responding to keyless entry (e.g., door handles not unlocking).

Step 1: Check the Key Fob Battery

Tools Required: Small flathead screwdriver or coin, new CR2032 battery.

  1. Open the Key Fob:

    • Use a flathead screwdriver or coin to gently pry open the key fob.
    • Remove the back cover, exposing the battery compartment.

  2. Inspect the Battery:

    • Check the orientation and condition of the battery.
    • If the battery is dead or weak, replace it with a new CR2032 battery.

  3. Reassemble the Key Fob:

    • Snap the key fob back together and test the keyless entry functions.

Step 2: Verify Key Fob Programming

  1. Reprogram the Key Fob:
    • Sit inside the vehicle with the key fob.
    • Insert the key into the ignition and turn to the "ON" position (do not start the engine).
    • Press and hold the lock button on the key fob for approximately 5-10 seconds.
    • Turn the ignition to "OFF," then back to "ON" and press the lock button again.
    • Check if the doors respond to the key fob.

Step 3: Inspect the Vehicle's Antenna and Modules

Tools Required: OBD-II scanner, basic hand tools, multimeter.

  1. Scan for Diagnostic Codes:

    • Connect an OBD-II scanner to the vehicle’s OBD-II port (usually under the dashboard).
    • Check for any DTCs (Diagnostic Trouble Codes) related to the keyless entry system.
    • Note any relevant codes (e.g., B1242, B1243).

  2. Visual Inspection:

    • Inspect the keyless entry antenna located near the roof or around the trunk area.
    • Check for damaged wiring or loose connections.

  3. Test the Antenna:

    • Use a multimeter to test the continuity of the antenna wiring.
    • If there is no continuity, repair or replace the wiring as necessary.

Step 4: Check for Interference

  1. Environmental Factors:

    • Move away from other electronic devices that might cause interference (e.g., radio towers, Wi-Fi routers).
    • Test the key fob in a different location to rule out interference.

  2. Alternate Key Fob:

    • If available, test with a second key fob to determine if the original is faulty.
Repair Instructions

If Key Fob Battery Replacement Does Not Work

  1. Reprogram the Key Fob:
    • Follow the reprogramming steps outlined above.
    • If unsuccessful, consider a visit to a dealership for advanced programming or synchronization.

If Antenna or Wiring Issues Are Detected

  1. Repair or Replace Wiring:

    • If damaged wiring is found, cut the damaged section and splice in new wiring using solder or crimp connectors.
    • Insulate all connections with electrical tape or heat-shrink tubing to prevent short circuits.

  2. Replace the Antenna:

    • If the antenna is defective, remove it by unscrewing any retaining screws and disconnecting it.
    • Install a new antenna by reversing the removal steps.

If No Issues Are Found

  1. Visit a Professional:
    • If all checks are clear and the keyless entry still does not work, schedule an appointment with a Toyota dealership or qualified automotive technician to diagnose potential software or module issues.
Final Checks
  • After repairs, test the keyless entry system from various distances.
  • Ensure all doors respond properly to the key fob and that the vehicle starts without issues.

By following these steps methodically, you should be able to diagnose and resolve keyless entry issues in your 2021 Toyota Highlander effectively.