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What are the common issues with the automatic headlights in the 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What are the common issues with the automatic headlights in the 2021 Toyota Highlander?

What are the common issues with the automatic headlights in the 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

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

Problem Statement

Learn about common issues with the automatic headlights in the 2021 Toyota Highlander, including symptoms, diagnostic steps, and repair instructions.

Affected Component
automatic headlights
Estimated Time
2-3 hours

Symptoms

  • •Headlights Not Turning On Automatically
  • •Headlights Staying On
  • •Inconsistent Functionality
  • •Error Messages

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

  • •OBD-II Scanner
  • •Multimeter
  • •Basic hand tools (screwdrivers, socket set)
  • •Cleaning materials (cloth, electrical contact cleaner)

Additional Information

Affected Component
automatic headlights
Estimated Time
2-3 hours
Difficulty
medium
Severity
medium
Tools Required
4 items

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Back to Generation
Common Issues with Automatic Headlights in the 2021 Toyota Highlander

The automatic headlight system in the 2021 Toyota Highlander can occasionally experience several common issues. Below are the symptoms, diagnostic steps, tools required, and repair instructions for addressing these problems.

Common Symptoms

  1. Headlights Not Turning On Automatically: The headlights fail to switch on when it gets dark.
  2. Headlights Staying On: The headlights remain illuminated even during daylight.
  3. Inconsistent Functionality: The automatic headlights work intermittently.
  4. Error Messages: Dashboard notifications about headlight malfunctions.

Step 1: Visual Inspection

  • Symptom Check: Verify if the headlights are functioning manually (using the headlight switch).
  • Sensor Assessment: Inspect the light sensor located on the dashboard near the windshield to ensure it’s not obstructed by dirt or debris.

Step 2: Check the Headlight Settings

  • Vehicle Settings: Access the vehicle settings via the infotainment system to confirm that the automatic headlight feature is enabled.

Step 3: Scan for Error Codes

  • OBD-II Scanner: Connect an OBD-II scanner to the vehicle’s diagnostic port. Note any codes related to the lighting system.

Step 4: Inspect Wiring and Connectors

  • Visual Inspection: Check wiring harnesses and connectors associated with the headlights for signs of wear, corrosion, or damage.
Tools Required
  • OBD-II Scanner
  • Multimeter
  • Basic hand tools (screwdrivers, socket set)
  • Cleaning materials (cloth, electrical contact cleaner)
Repair Instructions

Issue 1: Headlights Not Turning On Automatically

  1. Check Light Sensor:
    • Clean the light sensor. If it appears damaged, consider replacing it.
  2. Inspect Headlight Relay:
    • Locate the headlight relay in the fuse box (consult the owner’s manual).
    • Test the relay with a multimeter. Replace if faulty.

Issue 2: Headlights Staying On

  1. Headlight Switch Check:
    • Ensure the headlight switch is not in the ‘On’ or ‘Parking’ position.
  2. Software Update:
    • Check for any software updates that may resolve the issue. Visit a Toyota dealership if necessary.
  3. Replace Light Sensor:
    • If the sensor is faulty, replace it as described in the steps below.

Issue 3: Inconsistent Functionality

  1. Recalibration:
    • Disconnect the vehicle battery for about 10 minutes to reset the system. Reconnect and test.
  2. Check for Fault Codes:
    • Use the OBD-II scanner to identify any specific issues related to the automatic headlight system. Address any trouble codes found.

Issue 4: Error Messages

  1. Clear Codes:
    • If error codes are present, clear them with the OBD-II scanner and test the system again.
  2. Inspect for Faulty Components:
    • If error messages persist, inspect fuses related to the headlight system and replace them as needed.
Replacement of Light Sensor (if required)
  1. Locate the Sensor:
    • The light sensor is generally found on the top of the dashboard near the windshield.
  2. Remove Trim:
    • Carefully remove any trim pieces that obstruct access to the sensor.
  3. Disconnect the Sensor:
    • Unplug the sensor connector.
  4. Install New Sensor:
    • Connect the new sensor and secure it in place.
  5. Reassemble Trim:
    • Reinstall any trim pieces removed during the process.
Final Steps
  • Test the System: After repairs, conduct a thorough test of the automatic headlight functionality under varying light conditions.
  • Documentation: Keep a record of the issues, diagnostics performed, and repairs made for future reference.

By following these steps, you can effectively diagnose and repair common automatic headlight issues in a 2021 Toyota Highlander.