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How can I troubleshoot the blind spot monitoring system in my 2020 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How can I troubleshoot the blind spot monitoring system in my 2020 Toyota Highlander?

How can I troubleshoot the blind spot monitoring system in my 2020 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

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

Problem Statement

Learn how to troubleshoot and repair the Blind Spot Monitoring System in your 2020 Toyota Highlander with our step-by-step guide.

Affected Component
Blind Spot Monitoring System
Estimated Time
2-3 hours

Symptoms

  • •Blind Spot Monitoring (BSM) warning lights do not illuminate when a vehicle is in the blind spot.
  • •BSM system warning light on the dashboard is illuminated.
  • •The system does not provide audible alerts when a vehicle enters the blind spot.
  • •The BSM system intermittently fails to operate.

Diagnostic Steps

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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 Tool (Toyota Techstream or equivalent)
  • •Screwdrivers (Phillips and flat-head)
  • •Torx bits
  • •Safety gloves and goggles
  • •Wire connectors (if repairs are needed)
  • •Vehicle repair manual (for reference)

Additional Information

Affected Component
Blind Spot Monitoring System
Estimated Time
2-3 hours
Difficulty
medium
Severity
medium
Tools Required
8 items

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Back to Generation
Troubleshooting the Blind Spot Monitoring System in a 2020 Toyota Highlander
Tools Required
  • OBD-II Scanner
  • Multimeter
  • Diagnostic Tool (Toyota Techstream or equivalent)
  • Screwdrivers (Phillips and flat-head)
  • Torx bits
  • Safety gloves and goggles
  • Wire connectors (if repairs are needed)
  • Vehicle repair manual (for reference)

Step 1: Initial Inspection

  1. Visual Inspection of Sensors:

    • Check the rear bumper area for any visible damage.
    • Inspect the BSM sensors (usually located on the rear corners of the bumper) for dirt, debris, or obstructions.
    • Ensure that the sensors are aligned correctly and are not misaligned due to an impact.

  2. Check System Activation:

    • Ensure the BSM system is activated. Check the settings in the vehicle's multimedia system to confirm the BSM is turned on.

Step 2: Scan for Diagnostic Trouble Codes (DTC)

  1. Connect OBD-II Scanner:

    • Plug the OBD-II scanner into the vehicle’s diagnostic port, typically located under the dashboard on the driver's side.

  2. Retrieve Codes:

    • Use the scanner to read any stored trouble codes related to the BSM system.
    • Document any codes, as they will guide further troubleshooting.

Step 3: Electrical Diagnosis

  1. Inspect Wiring Harness:

    • Check the wiring harness connected to the BSM sensors for any signs of wear, damage, or corrosion.
    • Use a multimeter to test for continuity in the wiring.

  2. Check Power and Ground:

    • With the multimeter, check for voltage at the BSM sensor connectors. Ensure they are receiving the correct voltage (typically around 12V).
    • Verify that the ground connections are secure and free of corrosion.

Step 4: Sensor Functionality Test

  1. Test Sensors:
    • If equipped, use a diagnostic tool like Toyota Techstream to perform a sensor test. This will confirm whether the sensors are functioning correctly.
    • If any sensors are found to be faulty, they will need to be replaced.
Repair Instructions

Step 1: Cleaning or Replacing Sensors

  1. Cleaning Sensors:

    • If dirt or debris is found on the sensors, clean them carefully with a soft cloth and appropriate cleaner.

  2. Replacing Sensors:

    • If a sensor is confirmed faulty, follow these steps:
      1. Disconnect the battery to prevent electrical shorts.
      2. Remove the bumper cover (if necessary) using screwdrivers and Torx bits.
      3. Unplug the faulty sensor and remove it from its mount.
      4. Install the new sensor by reversing the removal steps.
      5. Reconnect the battery.

Step 2: Clearing Codes and Testing

  1. Clear DTCs:

    • Use the OBD-II scanner to clear any trouble codes.

  2. Test the System:

    • After repairs, take the vehicle for a test drive to confirm the BSM system is functioning properly. Check for warning lights and audible alerts.
Final Steps
  • If the BSM system still does not function correctly after all diagnostics and repairs, it may require further diagnosis by a professional dealership or qualified technician due to potential issues with the vehicle's ECU or programming.
Conclusion

By following these systematic steps, you can diagnose and potentially resolve issues with the Blind Spot Monitoring System in your 2020 Toyota Highlander. Always ensure safety during repairs and consult the vehicle's repair manual for specific technical details.