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

Tools Required

1. Flathead and Phillips Screwdrivers: For opening the key fob casing.
2. Multimeter: For checking battery voltage.
3. Replacement Battery: Typically a CR2032 or CR2016 (check your specific fob).
4. Owner’s Manual: For reprogramming instructions.
5. Key Fob Tester (optional): To test the signal strength and functionality.

Repair Instructions

Step 1: Open the Key Fob

1. Locate the Seam: Identify the seam on the key fob where it separates.
2. Use a Flathead Screwdriver: Gently insert the screwdriver into the seam and twist to pry open the fob.
3. Be Cautious: Avoid damaging the casing or internal components.

Step 2: Replace the Battery

1. Remove the Old Battery: Note the orientation (positive and negative sides) and carefully remove the old battery.
2. Insert the New Battery: Place the new battery in the same orientation as the old one.
3. Ensure Proper Contact: Make sure the battery contacts are clean and secure.

Step 3: Close the Key Fob

1. Align the Two Halves: Ensure that the internal components are properly aligned before closing.
2. Press Together Firmly: Snap the two halves back together until you hear a click.

Step 4: Test the Key Fob

1. Stand Close to the Vehicle: Test the lock, unlock, and remote start functions.
2. Use the Multimeter: If issues persist, check the new battery voltage.
3. Check for Response: If the vehicle still does not respond, proceed to reprogram the fob.

Step 5: Reprogram the Key Fob (if necessary)

1. Insert the Key: Insert the key into the ignition and turn it to the “ON” position (do not start).
2. Press the Lock Button: On the fob, press the lock button for 5 seconds.
3. Turn Off the Ignition: Turn the key back to the “OFF” position.
4. Repeat: This may need to be repeated a few times (check the manual for the exact sequence).
5. Test Again: After programming, test all functions of the key fob again.

Conclusion

If after all these steps the key fob still does not function correctly, it may be necessary to consult with a professional or visit a Toyota dealership for further diagnostics or replacement. In some cases, the issue could be with the vehicle's keyless entry system rather than the fob itself. Always ensure you have backup keys available in case of emergencies.