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How do I fix the malfunctioning headlights in my 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How do I fix the malfunctioning headlights in my 2021 Toyota Highlander?

How do I fix the malfunctioning headlights in my 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
583 words

Problem Statement

Learn how to diagnose and fix malfunctioning headlights in your 2021 Toyota Highlander with step-by-step instructions.

Affected Component
headlights

Symptoms

  • •Headlights are completely non-functional.
  • •One headlight is out while the other works.
  • •Flickering or dim headlights.
  • •Headlights turning off or on intermittently.

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
  • •Screwdrivers (flat and Phillips)
  • •Pliers
  • •Replacement headlight bulbs (if needed)
  • •Replacement fuses (if needed)
  • •Electrical contact cleaner (optional)
  • •Work gloves
  • •Safety glasses

Additional Information

Affected Component
headlights
Difficulty
medium
Severity
medium
Tools Required
8 items

Related Faults

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Back to Generation
Fixing Malfunctioning Headlights in a 2021 Toyota Highlander
Tools Required
  • Multimeter
  • Screwdrivers (flat and Phillips)
  • Pliers
  • Replacement headlight bulbs (if needed)
  • Replacement fuses (if needed)
  • Electrical contact cleaner (optional)
  • Work gloves
  • Safety glasses

Repair Instructions

  1. Replace Headlight Bulbs (if necessary)

    • Remove the headlight assembly:
      • Open the hood and locate the headlight assembly.
      • Unscrew or unclip the assembly from the mounting points.
    • Disconnect the wiring harness:
      • Carefully pull the connector out of the bulb socket.
    • Replace the bulb:
      • Twist the bulb counterclockwise to remove it.
      • Insert a new bulb (do not touch the glass with bare fingers).
      • Reconnect the wiring harness securely.
    • Reinstall the headlight assembly:
      • Secure it back into position with screws or clips.

  2. Replace Blown Fuses (if necessary)

    • Use a fuse puller or pliers to remove the blown fuse.
    • Insert a new fuse of the same amperage into the correct slot.
    • Test the headlights again to see if they function properly.

  3. Repair or Replace Wiring/Connectors (if necessary)

    • If you identified damaged wiring or connectors, repair or replace them as needed.
    • Use electrical contact cleaner on corroded connectors to ensure a good connection.

  4. Replace Headlight Relay (if necessary)

    • If swapping the relay resolved the issue, replace the faulty relay with a new one.
    • Secure it back into the fuse box.

  5. Final Testing

    • After making all necessary repairs, turn on the headlights.
    • Test all functions — low beam, high beam, and turn signals.
    • Check the alignment of the headlights to ensure proper illumination on the road.
Conclusion

By following these steps, you should be able to diagnose and fix the malfunctioning headlights in your 2021 Toyota Highlander. If the problem persists after performing these checks and repairs, it may be advisable to consult a professional technician or visit a Toyota dealership for further assistance.