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

What are the common electrical issues in the 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
5 min read
832 words

Problem Statement

Explore common electrical issues in the 2021 Toyota Highlander, including symptoms, diagnostic steps, and repair instructions.

Affected Component
Electrical System

Symptoms

  • •Vehicle won't start after sitting for a few days.
  • •Dim interior lights.
  • •Malfunctioning electronic accessories.
  • •Windows do not respond to switch commands.
  • •Windows may operate intermittently.
  • •Screen freezes or remains blank.
  • •Bluetooth connection issues.
  • •Audio system malfunctions.
  • •Various lights illuminated on the dashboard (e.g., check engine, battery, ABS).
  • •Difficulty locking/unlocking doors.
  • •Key fob not recognized by the vehicle.

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

  • •Digital Multimeter
  • •Wrench Set
  • •Wire Brush (for terminals)
  • •Screwdrivers (Philips and Flathead)
  • •Torx Bits
  • •OBD-II Scanner
  • •Basic Hand Tools
  • •Small Phillips Screwdriver
  • •New Battery (CR2032 or similar, depending on the fob)

Additional Information

Affected Component
Electrical System
Difficulty
medium
Severity
medium
Tools Required
9 items

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Back to Generation
Common Electrical Issues in the 2021 Toyota Highlander

The 2021 Toyota Highlander, part of the fourth generation (XU70), may experience several common electrical issues. Below is a detailed overview of these issues, including symptoms, diagnostic steps, tools required, and repair instructions.

Common Electrical Issues
  1. Battery Drain
  2. Faulty Power Windows
  3. Malfunctioning Infotainment System
  4. Warning Lights on Dashboard
  5. Key Fob Issues
1. Battery Drain
Tools Required
  • Digital Multimeter
  • Wrench Set
  • Wire Brush (for terminals)
Repair Instructions
  1. Clean Battery Terminals: Use the wire brush to clean corroded terminals.
  2. Identify Parasitic Draw:
    • Pull fuses one at a time to identify which circuit is causing excessive draw.
  3. Repair or Replace Faulty Component: Depending on the identified circuit, repair or replace components as necessary (e.g., light switches, modules).
  4. Battery Replacement: If the battery is weak or not holding a charge, replace with a new battery.
2. Faulty Power Windows
Tools Required
  • Digital Multimeter
  • Screwdrivers (Philips and Flathead)
  • Torx Bits
Repair Instructions
  1. Replace Window Switch: If the switch is faulty, replace it by removing the door panel and disconnecting the switch connector.
  2. Inspect/Replace Window Motor: If the motor is not receiving power, check the wiring for continuity. If the motor is faulty, remove the door panel, disconnect the motor, and replace it.
  3. Check Fuses: Inspect and replace any blown fuses related to the window operation.
3. Malfunctioning Infotainment System
Tools Required
  • OBD-II Scanner (for software issues)
  • Torx Bits (for removing the head unit)
Repair Instructions
  1. Update Software: Check Toyota’s official website for software updates and follow instructions to update.
  2. Reconnect Wiring: If loose or damaged connectors are found, reconnect or repair them.
  3. Replace Unit: If the system is non-functional after all checks, consider replacing the head unit.
4. Warning Lights on Dashboard
Tools Required
  • OBD-II Scanner
  • Multimeter
  • Basic Hand Tools
Repair Instructions
  1. Address Trouble Codes: Research the trouble codes and address the underlying issues (e.g., sensor replacements, wiring repairs).
  2. Clear Codes: After repairs, use the scanner to clear the codes and see if they return.
  3. Check Battery and Alternator: Ensure the alternator is charging correctly (ideally around 14 volts while running) and that the battery is in good condition.
5. Key Fob Issues
Tools Required
  • Small Phillips Screwdriver
  • New Battery (CR2032 or similar, depending on the fob)
Repair Instructions
  1. Replace Battery: If the battery is dead, replace it and reassemble the fob.
  2. Reprogram: Follow the specific reprogramming steps found in the owner’s manual (may involve turning the ignition on/off in a sequence).
  3. Test Functionality: After reprogramming, check to ensure all functions of the key fob work correctly.

By following these guidelines, you can effectively diagnose and address common electrical issues in the 2021 Toyota Highlander. Always refer to the vehicle's service manual for specific instructions and safety precautions.