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Are there any known electrical faults in the 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/Are there any known electrical faults in the 2021 Toyota Highlander?

Are there any known electrical faults in the 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

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

Problem Statement

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

Affected Component
Electrical System

Symptoms

  • •Battery Drain
  • •Dashboard Warning Lights
  • •Malfunctioning Infotainment System
  • •Key Fob Issues
  • •Power Window Failures
  • •Failed Sensors

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

  • •Multimeter
  • •Circuit Tester
  • •Basic Hand Tools (screwdrivers, wrenches)
  • •OBD-II Scanner
  • •Key Fob Tester (optional)

Additional Information

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

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Back to Generation
Known Electrical Faults in the 2021 Toyota Highlander

The 2021 Toyota Highlander, part of the fourth generation (XU70), has been reported to have several electrical issues. While not exhaustive, the following are some common symptoms, diagnostic steps, tools required, and potential repair instructions for these electrical faults.

Common Symptoms of Electrical Issues

  1. Battery Drain: The vehicle may exhibit rapid battery drain, often due to parasitic draws.
  2. Dashboard Warning Lights: Unexpected illumination of dashboard warning lights, such as the battery or check engine light.
  3. Malfunctioning Infotainment System: The multimedia system may freeze, reboot, or fail to operate correctly.
  4. Key Fob Issues: Difficulty in locking/unlocking doors or starting the vehicle with the key fob.
  5. Power Window Failures: Windows may not respond to controls or operate slowly.
  6. Failed Sensors: Issues with parking sensors, lane departure warnings, or other electronic safety features.

Step 1: Visual Inspection

  • Tools Required: Multimeter, circuit tester, basic hand tools (screwdrivers, wrenches).
  • Action: Inspect battery terminals and connections for corrosion or looseness. Check fuses for any blown components in the fuse box.

Step 2: Battery and Charging System Test

  • Tools Required: Multimeter.
  • Action:
    1. With the vehicle off, measure the battery voltage. It should read between 12.4V to 12.6V.
    2. Start the vehicle and measure the voltage again. It should read between 13.7V to 14.7V, indicating the alternator is charging properly.

Step 3: Parasitic Draw Test

  • Tools Required: Multimeter.
  • Action:
    1. Ensure the vehicle is turned off and all accessories are off.
    2. Disconnect the negative battery terminal.
    3. Set the multimeter to the DC amps setting and connect it in series with the negative battery cable and terminal.
    4. The reading should be below 50 mA. If it's higher, check for systems that remain powered (e.g., glove box light, trunk lights).

Step 4: Infotainment System Diagnostics

  • Tools Required: OBD-II scanner.
  • Action:
    1. Connect the OBD-II scanner to the vehicle's diagnostic port.
    2. Retrieve any trouble codes that might be related to the infotainment system or other electrical components.
    3. Note any codes and refer to repair manuals for specific troubleshooting based on the codes.

Step 5: Key Fob Testing

  • Tools Required: Key fob tester (optional) or multimeter.
  • Action:
    1. Test the key fob battery with a multimeter. The battery voltage should be around 3V.
    2. If the battery is low, replace it and test the key fob functionality again.
Repair Instructions

Repairing Battery Drain Issues

  1. Identify the Source:
    • Use the parasitic draw test to identify circuits that are drawing excessive current.
  2. Repair:
    • For any faulty components causing the draw, replace or repair them based on the circuit diagrams.

Fixing Infotainment System Problems

  1. Software Update:
    • Check for any available software updates from Toyota.
    • Use the dealer or a professional service to perform updates if required.
  2. Component Replacement:
    • If specific components (like the head unit or wiring) are faulty, consult the service manual for replacement procedures.

Key Fob Battery Replacement

  1. Open the Key Fob:
    • Use a small screwdriver to pry open the key fob casing.
  2. Replace the Battery:
    • Remove the old battery and insert the new battery in the correct orientation.
  3. Reassemble and Test:
    • Reassemble the key fob and test functionality on the vehicle.

Power Window Repair

  1. Check Window Switches:
    • Use a multimeter to test the window switches for continuity.
  2. Inspect Wiring:
    • Check the wiring harnesses for any signs of damage or corrosion.
  3. Replace Components:
    • If switches or motors are faulty, replace them per the service manual instructions.
Conclusion

If the issues persist after these diagnostics and repairs, it is advisable to consult a professional technician or visit a Toyota dealership for further assistance, as they may have access to more advanced diagnostic tools and proprietary information.