FAULTBASE
Error CodesASKCars
© 2026 FAULTBASE
All rights reserved.
v2.0.0 • Production
ContactPrivacyImpressum
How can I troubleshoot a malfunctioning key fob for my Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How can I troubleshoot a malfunctioning key fob for my Highlander?

How can I troubleshoot a malfunctioning key fob for my Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
1 hour
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
571 words

Problem Statement

Learn how to troubleshoot and fix a malfunctioning key fob for your Toyota Highlander with step-by-step instructions.

Affected Component
key fob
Estimated Time
1 hour

Symptoms

  • •Key fob not responding
  • •Erratic behavior
  • •Battery warning light
  • •No response to remote start

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

  • •Small flathead screwdriver
  • •New battery (CR2032 or as specified in your vehicle’s manual)
  • •Owner’s manual for specific programming instructions
  • •A second working key fob (if available)
  • •OBD-II scanner (optional)

Additional Information

Affected Component
key fob
Estimated Time
1 hour
Difficulty
medium
Severity
medium
Tools Required
5 items

Related Faults

Loading...

Share this solution

Comments

Sign in to share your thoughts

Sign In

No comments yet

Be the first to share your thoughts

Back to Generation

Troubleshooting a Malfunctioning Key Fob for Toyota Highlander (2020-present)

Step 1: Check the Battery
  1. Inspect the key fob: Look for any physical damage or wear.
  2. Test the battery:
    • Use a multimeter to check the voltage of the key fob battery. Most key fobs use a CR2032 or similar lithium battery.
    • A healthy battery should read approximately 3.0 volts.
    • If the voltage is significantly lower (below 2.7 volts), replace the battery.
Step 2: Replace the Battery

Tools Required:

  • Small flathead screwdriver
  • New battery (CR2032 or as specified in your vehicle’s manual)

Instructions:

  1. Open the key fob:
    • Use the small flathead screwdriver to pry open the key fob along the seam.
  2. Remove old battery: Take note of the battery orientation (positive and negative sides).
  3. Install new battery: Insert the new battery in the same orientation as the old one.
  4. Reassemble the key fob: Snap the two halves back together until securely closed.
Step 3: Reprogram the Key Fob

If the key fob still doesn't work after replacing the battery, it may need reprogramming.

Tools Required:

  • Owner’s manual for specific programming instructions
  • A second working key fob (if available)

Instructions:

  1. Enter the vehicle: Close all doors and ensure the vehicle is in 'Park'.
  2. Insert the key: Insert the key into the ignition without starting the engine.
  3. Turn the key: Turn the key to 'On' (do not start) and then back to 'Off' five times within 10 seconds. The vehicle lights should flash, confirming it is in programming mode.
  4. Press the lock button: Press and hold the 'Lock' button on the key fob for about 5 seconds.
  5. Turn off the ignition: After programming, turn the key to 'Off' and remove it from the ignition.
  6. Test the key fob: Step outside and test the key fob to see if it locks/unlocks the doors.
Step 4: Check for Interference

Instructions:

  1. Move away from potential interference: Certain electronic devices can cause issues with key fob signals. Move away from devices like Wi-Fi routers, microwaves, or other vehicles.
  2. Try your key fob in various locations: Test the fob in different areas to rule out signal interference.
Step 5: Check the Vehicle Receiver

If the key fob still malfunctions:

  1. Inspect the vehicle’s receiver:
    • Check for blown fuses related to the keyless entry system. Refer to the owner’s manual for the location of the fuse box and the specific fuse.
    • If a fuse is blown, replace it with the same amperage rating.
  2. Diagnose with a scan tool:
    • If you have access to an OBD-II scanner, connect it to the vehicle and check for any trouble codes related to the keyless entry system. Follow specific troubleshooting for any codes that appear.
Conclusion

After following these steps, your key fob should be functioning correctly. If issues persist, it may be necessary to consult a certified Toyota technician for further diagnostics, as there may be an underlying electrical issue or the key fob itself may need replacement.