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How can I troubleshoot the headlights not turning on in my 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How can I troubleshoot the headlights not turning on in my 2021 Toyota Highlander?

How can I troubleshoot the headlights not turning on in my 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
1-2 hours
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
592 words

Problem Statement

Learn how to troubleshoot and fix headlights not turning on in your 2021 Toyota Highlander with step-by-step diagnostic and repair instructions.

Affected Component
headlights
Estimated Time
1-2 hours

Symptoms

  • •Headlights not illuminating
  • •Dashboard indicator may or may not indicate a headlight issue
  • •Other lights functioning

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6

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

  • •Fuse puller or needle-nose pliers
  • •Phillips screwdriver
  • •Multimeter
  • •OBD-II scanner

Additional Information

Affected Component
headlights
Estimated Time
1-2 hours
Difficulty
medium
Severity
medium
Tools Required
4 items

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Troubleshooting Headlights Not Turning On in a 2021 Toyota Highlander
Repair Instructions

  1. Replacing a Blown Fuse

    • Action: Remove the blown fuse with a fuse puller.
    • Replacement: Insert a new fuse of the same amperage.

  2. Replacing Headlight Bulbs

    • Action: Follow these steps for bulb replacement:
      • Disconnect the vehicle battery (negative terminal).
      • Remove the headlight assembly by unscrewing the retaining screws.
      • Unplug the bulb connector and remove the old bulb.
      • Insert the new bulb without touching the glass.
      • Reconnect the bulb and reassemble the headlight assembly.

  3. Repairing Wiring Issues

    • Action: If any wiring is damaged, splice in new wiring or use electrical tape to secure any frayed areas. Ensure all connections are tight and insulated.

  4. Replacing the Headlight Relay

    • Action: Remove the faulty relay by pulling it directly out of the socket.
    • Replacement: Insert a new relay in the same position.

  5. Addressing BCM Issues

    • If the BCM is diagnosed as faulty:
      • Consult a professional technician for replacement or reprogramming, as this may require specialized tools and knowledge.
Final Steps
  • Reconnect the Battery: Ensure all connections are tight and reattach the negative battery terminal.
  • Test the Headlights: Turn on the headlights to ensure they are functioning properly.
  • Perform a Visual Inspection: Check other lighting systems to ensure they are operational.
Conclusion

If, after following these steps, the headlights still do not work, further investigation may be required, potentially involving professional diagnostic equipment and expertise.