How to Replace the Battery in a Lexus ES 350 FOB Key

Manufactured by the Toyota Motor Corporation's luxury vehicles brand, Lexus ES-series vehicles are entry-level mid-sized luxury sedans that have been in production since 1989. Released for the 2007 model year, the Lexus ES350 kicked off the fifth generation of ES vehicles and featured a stylish redesign, as well as convenient optional features such as a keyless entry system. When the battery in your Lexus ES350 keyless entry fob dies, you can complete the battery replacement process in just minutes.

Things You'll Need

  • Replacement CR2032 battery
  • Locate the small silver switch on the bottom of your Lexus ES350 keyless entry fob. Slide the switch all the way to the right and remove the mechanical key from the electronic fob.

  • Examine the keyless entry fob to locate the small groove that was revealed by removing the mechanical key. Insert the tip of the mechanical key into the groove and work it back and forth until the halves of the electronic fob separate.

  • Use the tip of the mechanical key to pry the old battery out of the battery compartment; insert a new CR2032 battery, making sure to observe the correct polarity. Note that the battery compartment is mounted to the back of the circuit board in the electronic fob.

  • Align the two halves of the electronic keyless entry fob. Use your fingers to apply gentle to moderate pressure to both halves of the fob until they snap together.

  • Reinsert the mechanical key into the Lexus ES350 electronic fob. Push in the mechanical key until you hear it click into place.