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What are the common problems with the adaptive cruise control in the Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What are the common problems with the adaptive cruise control in the Highlander?

What are the common problems with the adaptive cruise control in the Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
656 words

Problem Statement

Explore common issues with the adaptive cruise control system in the Toyota Highlander, including symptoms, diagnostic steps, and repair instructions.

Affected Component
adaptive cruise control system

Symptoms

  • •Inconsistent Speed Control
  • •False Alerts
  • •ACC Not Engaging
  • •Erratic Braking
  • •Detection Issues

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  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
  • •Torque wrench
  • •Cleaning cloth
  • •Vehicle owner's manual
  • •Toyota Techstream or equivalent diagnostic tool
  • •Brake inspection tools (jack, jack stands, etc.)

Additional Information

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

Related Faults

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Common Problems with Adaptive Cruise Control in the Toyota Highlander (Fourth Generation)

The adaptive cruise control (ACC) system in the Toyota Highlander (2020-present) is designed to automatically adjust the vehicle's speed to maintain a safe distance from the vehicle ahead. While generally reliable, there are some common issues that can arise with this system.

Common Symptoms

  1. Inconsistent Speed Control: The vehicle may not maintain the set speed or might accelerate/decelerate unexpectedly.
  2. False Alerts: Warning lights or messages on the dashboard indicating a system malfunction when there is none.
  3. ACC Not Engaging: The system fails to activate when the cruise control button is pressed.
  4. Erratic Braking: The vehicle may apply brakes unexpectedly when the road is clear.
  5. Detection Issues: The system does not detect vehicles in front correctly, leading to erratic behavior.
Repair Instructions

  1. Addressing Warning Lights

    • If DTCs are found, follow the repair procedures according to the codes. This may involve replacing faulty sensors or wiring.

  2. Radar Sensor Replacement

    • If the radar sensor is damaged:
      • Disconnect the battery.
      • Remove the mounting bolts and disconnect the wiring harness.
      • Install the new radar sensor, connect the wiring harness, and secure it with bolts.
      • Reconnect the battery and perform calibration.

  3. Updating Software

    • If the system is not functioning as expected, check for software updates:
      • Use the Toyota Techstream or contact a dealership to perform software updates related to the ACC system.

  4. Brake System Repair

    • If brake components are worn or damaged:
      • Replace brake pads, rotors, or fluid as necessary.
      • Ensure the brake system is functioning correctly before re-testing the ACC.

  5. Final Test

    • After addressing the issues, conduct a test drive to verify that the ACC system is functioning correctly. Monitor for any warning lights and check the responsiveness of the system.
Conclusion

By following these diagnostic steps and repair instructions, you can effectively troubleshoot and resolve common issues related to the adaptive cruise control in the Toyota Highlander (2020-present). Ensure to refer to the owner's manual and service documentation for any specific details related to your vehicle's configuration.