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Are there any known issues with the adaptive cruise control in the 2021 Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/Are there any known issues with the adaptive cruise control in the 2021 Highlander?

Are there any known issues with the adaptive cruise control in the 2021 Highlander?

Toyota Highlander Fourth Generation (2020-present)

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

Problem Statement

Discover common issues, symptoms, diagnostic steps, and repair instructions for the adaptive cruise control system in the 2021 Toyota Highlander.

Affected Component
adaptive cruise control system

Symptoms

  • •Adaptive Cruise Control Not Engaging
  • •Inconsistent Speed Maintenance
  • •Unexpected Braking
  • •Warning Lights
  • •System Disabling

Diagnostic Steps

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  4. 4
  5. 5

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
  • •diagnostic scan tool
  • •screwdrivers
  • •socket set
  • •trim removal tools

Additional Information

Affected Component
adaptive cruise control system
Difficulty
medium
Severity
medium
Tools Required
6 items

Related Faults

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Back to Generation
Known Issues with the Adaptive Cruise Control in the 2021 Toyota Highlander

The 2021 Toyota Highlander, part of the fourth generation (XU70), has generally received positive reviews for its adaptive cruise control (ACC) system. However, like any sophisticated electronic system, it can encounter issues. Below are some common symptoms, diagnostic steps, tools required, and possible repair instructions for problems related to the adaptive cruise control.

Common Symptoms

  1. Adaptive Cruise Control Not Engaging: The system fails to activate when the cruise control button is pressed.
  2. Inconsistent Speed Maintenance: The vehicle does not maintain the set speed or fluctuates unexpectedly.
  3. Unexpected Braking: The system applies brakes without a clear reason.
  4. Warning Lights: Dashboard indicators for cruise control or lane departure warning may illuminate.
  5. System Disabling: The ACC system turns off unexpectedly.
Repair Instructions

  1. Cleaning Sensors:

    • If any dirt or debris is found on the radar or camera sensors, clean them gently with a microfiber cloth.
    • Ensure that the sensors are unobstructed for optimal performance.

  2. Replacing Faulty Switch:

    • If the cruise control switch is faulty:
      1. Tools Required: Screwdrivers, socket set, trim removal tools.
      2. Disconnect the negative battery terminal.
      3. Remove the steering column cover.
      4. Unscrew and disconnect the old cruise control switch.
      5. Install the new switch and reassemble the steering column.

  3. Calibrating Sensors:

    • If the sensors were found to be misaligned or non-functional:
      1. Use the manufacturer’s service manual for calibration instructions.
      2. This typically requires specialized equipment to recalibrate the radar and camera systems.

  4. Updating Software:

    • If the DTCs indicate software issues:
      • Visit the dealership or a certified technician to perform a software update on the vehicle’s ECU.
      • Ensure that the latest firmware is installed for all relevant systems.

  5. Addressing Fault Codes:

    • If specific codes are retrieved, refer to the factory service manual for troubleshooting procedures related to those codes.
    • Address each issue systematically based on the diagnostic results.

Conclusion

If issues persist after following these steps, it is advisable to consult a certified Toyota technician or take the vehicle to a dealership. The adaptive cruise control system is complex and may require specialized tools and knowledge for advanced diagnostics and repairs. Regular maintenance and prompt attention to warning indicators can help ensure the smooth operation of the ACC system in your 2021 Toyota Highlander.