2005 Lexus LS 430 Owners Manual - Page 50

KEYS AND DOORS A transponder chip for the engine immobilizer system has been placed in the master and valet keys. These chips are required for the system to function correctly, so be careful not to lose these keys. If you make your own duplicate key, you will not be able to cancel the system or start the engine. To protect items locked in the trunk or glove box when using valet parking, leave the valet key with the attendant. Since the doors and the trunk lid can be locked without a key, you should always carry a spare master key in case you accidentally lock your keys inside the vehicle. If you should lose your keys or if you need additional keys, duplicates can be made by a Lexus dealer using the key number. We recommend writing down the key number and storing it in a safe place. Flat keys 11L250 " 1 Mechanical flat key 2 Engine start flat key A mechanical flat key and an engine start flat key are included in the key case. Both flat keys are not equipped with smart key system. The mechanical flat key works in every lock, but cannot be used to start the engine. As a transponder chip is built in the engine start flat key, you can start the engine only with this key. A transponder chip for the engine immobilizer system has been placed in the engine start flat key. This chip is required for the system to function correctly, so be careful not to lose this key. If you make your own duplicate key, you will not be able to cancel the system or start the engine. Insert your flat key plates in its key case as shown. We recommend that you always carry this with you for emergency use. Do not leave it in your vehicle. 11