<h1>2021 Lexus LS500h Keyless Entry Remote Fob (Smart Key)</h1> <p><font size="3"><b> Important:</b> The 2021 Lexus LS500h does not support onboard programming for smart key remote fobs. Programming must be performed by a qualified technician using specialized diagnostic equipment. </font></p> <p><font size="3"><b>Step-by-Step Programming Instructions:</b></font></p> <ul> <li><font size="3"> Step 1: Confirm that the replacement smart key fob is compatible with the 2021 Lexus LS500h and has not been previously programmed to another vehicle. </font></li> <li><font size="3">Step 2: Schedule service with a certified technician who is experienced in Lexus key systems and equipped with the required diagnostic tools. </font></li> <li><font size="3">Step 3: Ensure that the technician uses secure, manufacturer-approved software capable of accessing the vehicle’s electronic control unit and key registration system. </font></li> <li><font size="3">Step 4: If your vehicle is operational, consider driving it to the technician’s service location to reduce any additional charges typically associated with mobile programming. </font></li> <li><font size="3">Step 5: Bring all currently functioning smart keys to the service appointment. Some Lexus systems may require all remotes to be present during the programming to ensure they remain active. </font></li> <li><font size="3">Step 6: The technician will connect a diagnostic interface to the vehicle’s onboard diagnostic port, typically located beneath the dashboard. </font></li> <li><font size="3">Step 7: Using the correct diagnostic software, the technician will initiate the programming process and securely pair the new smart key fob to the vehicle’s system. </font></li> <li><font size="3">Step 8: Once programming is complete, the technician will verify that all key functions—including locking, unlocking, trunk release, and push-button start—are working correctly. </font></li> <li><font size="3">Step 9: Additional remotes can typically be programmed during the same session if needed. </font></li> <li><font size="3">Step 10: Before concluding the service, verify that all programmed smart keys are functioning correctly and that the vehicle responds accurately to each key.</font></li> </ul>