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

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.