Are you looking to program a new key fob for your 2004 Lexus LS430? It’s a common need, whether you want a spare, or you’ve lost your original. While some might suggest complicated procedures involving gas pedals and brake tapping, the reality is that programming your Lexus LS430 key can be straightforward with the right methods. This guide will walk you through proven techniques to program both the transponder chip for starting your car and the remote functions of your 2004 Lexus Ls430 Key Fob.
Programming the Transponder Chip (Key Start)
These methods are designed to program the transponder chip within your new key, enabling it to start your 2004 Lexus LS430. You will need at least one working master key for these procedures.
Method 1: Using Accelerator and Brake Pedals
This method is effective for registering a new key to start your vehicle.
- Enter and Prepare: Get into your 2004 Lexus LS430 with your existing master key and ensure all doors are closed.
- Pedal Sequence Start: Simultaneously press and release both the brake and accelerator pedals once.
- Ignition Ready: Within 5 seconds, insert your existing master key into the ignition. Do not turn the key.
- Accelerator Pedal Presses: Within 15 seconds of key insertion, depress and release the accelerator pedal 5 times.
- Brake Pedal Presses: Within 20 seconds, depress and release the brake pedal 6 times. Then, remove the existing master key from the ignition.
- Insert New Key: Within 10 seconds, insert the new, unprogrammed 2004 Lexus LS430 key into the ignition.
- Final Accelerator Press: Depress and release the accelerator pedal one time. At this stage, the security light on your dashboard should begin to flash. This indicates that the car’s computer is recognizing the new key and initiating the programming sequence.
- Wait and Register: Leave the new key in the ignition for approximately 80 seconds, or until the security light stops flashing. Once the light stops, the new key is registered. Remove the new key.
- Complete and Test: Depress and release the brake pedal one time to finalize the programming process.
- Verify Key Start: Test the newly programmed 2004 Lexus LS430 key by inserting it into the ignition and attempting to start your car.
Method 2: Ignition and Door Cycling
This is an alternative method to program the transponder chip using ignition and door cycling.
- Prepare Vehicle: Ensure all doors and windows of your 2004 Lexus LS430 are fully closed.
- Master Key Ignition Cycle: Insert your working master key into the ignition cylinder. Cycle the ignition from the “On” position to “OFF” five times in quick succession.
- Driver Door Cycle: Open and close the driver’s side door 6 times.
- Replace with New Key: Remove the master key and immediately insert the new, duplicate 2004 Lexus LS430 key into the ignition.
- Turn Ignition ON: Turn the ignition cylinder to the “ON” position with the new key.
- Wait for Registration: Wait for approximately 60 seconds. The “THEFT” light on the dashboard should turn off, indicating that the programming of the new key is complete.
Programming the Remote Functions (Lock/Unlock)
Once the transponder chip is programmed, you may need to program the remote functions of your 2004 Lexus LS430 key fob to lock and unlock your doors remotely. Here are two methods for remote programming.
Method 1: Manual Lock Switch Cycling
This method utilizes the manual lock switch on the driver’s door for remote programming.
- Initial Setup: Sit in the driver’s seat of your 2004 Lexus LS430 and lock all doors using the power lock switch.
- Unlock and Open Driver Door: Unlock and open the driver’s door using the manual lock.
- Key Insertion (No Turn): Insert your 2004 Lexus LS430 key into the ignition, then immediately remove it. Do not turn the ignition on.
- Manual Lock Cycle (5 Times): Using the MANUAL lock switch on the driver’s door panel, lock and unlock the door 5 times.
- Close Driver Door: Close the driver’s door.
- Open Driver Door: Open the driver’s door again.
- Manual Lock Cycle (5 Times Again) & Ignition ON: Lock and unlock the driver’s door 5 more times using the MANUAL lock switch. Insert the key into the ignition and turn it to the “ON” position. Then remove the key from the ignition.
- Automatic Lock Cycle Confirmation: The driver’s door locks should now automatically cycle lock and unlock one time, confirming programming mode.
- Press and Hold “LOCK” Button (Attempt 1): On your 2004 Lexus LS430 key fob, press and hold the “LOCK” button for at least 1 second.
- Close Driver Door (Attempt 1): Close the driver’s door.
- Open Driver Door (Attempt 2): Open the driver’s door again.
- Press and Hold “LOCK” Button (Attempt 2): Press and hold the “LOCK” button on the key fob for at least one second again.
- Close Driver Door (Final Attempt): Close the driver’s door.
- Lock Confirmation: Press and hold the “LOCK” button on the key fob. The doors should lock, confirming successful programming.
- Unlock Confirmation: Press and hold the “LOCK” button on the key fob again. The doors should unlock.
Method 2: Key Insertion and Door Cycling (Simplified Remote Programming)
This method provides a potentially quicker way to program the remote functions.
- Driver Door Open & Key Out: Ensure the driver’s door is open and unlocked, and the key is out of the ignition.
- Insert and Remove Key (Twice): Insert the 2004 Lexus LS430 key into the ignition and remove it twice within 5 seconds.
- Close and Open Door (Twice – Set 1): Close and open the driver door twice within 40 seconds.
- Insert and Remove Key (Once): Insert the key into the ignition and remove it one more time.
- Close and Open Door (Twice – Set 2): Close and open the driver door twice again within 40 seconds.
- Insert Key and Close Door: Insert the key into the ignition, and then close the driver door.
- Ignition Cycling for Mode Selection: Turn the ignition to the “ON” position and back to “LOCK” in 1-second intervals. Cycle the ignition based on the mode you want:
- 1 time for Add mode
- 2 times for Rewrite mode
- 3 times for Confirmation mode
- 5 times for Prohibition mode (Note: There is no “4” mode in this sequence.)
- Remove Key and Confirmation Cycle: Remove the key from the ignition. The power locks should cycle automatically to confirm the mode selection.
- Remote Programming Sequence (Add or Rewrite Modes): If you are in “Add” or “Rewrite” mode (within 40 seconds of the confirmation cycle):
- A. Press Both Buttons: Press and hold both the “LOCK” and “UNLOCK” buttons on your 2004 Lexus LS430 key fob simultaneously for 1 to 1.5 seconds.
- B. Press “LOCK” Button: Within 3 seconds, press and hold the “LOCK” button for more than 1 second and then release.
- C. Programming Confirmation: If the programming is successful, the power door locks will cycle once. If unsuccessful, the door locks will cycle twice.
By following these methods, you should be able to program your 2004 Lexus LS430 key fob for both starting the vehicle and using the remote functions. Remember to test all functions after programming to ensure success.
