Here it is......
Basically, every lexus key has two functions: start the engine(immobilizer) and remote control (lock unlock doors, activate/deactivate alarm)
to program the immobilizer bit of your new key:
first, have your new key cut. Then:
For 1998+ Toyota, Lexus
Add Duplicate Key
1. Simultaneously depress and release brake and accelerator pedals 1 time.
2. Insert existing master key into ignition.
3. Within 15 seconds depress and release accelerator pedal 5 times.
4. Within 20 seconds depress and release the brake pedal 6 times and
5. Within 10 seconds insert new key into ignition.
6. Within 10 seconds depress and release the accelerator pedal 1 time.
7. After 80 seconds new key is registered and security light goes off.
8. Remove new key and depress and release brake pedal 1 time.
For 2002+ Toyota, Lexus
Add Duplicate Key
Requires one working Toyota/Lexus Master Key.
1. Make sure all doors and windows are closed.
2. Insert Master key into the ignition cylinder.
3. Cycle the ignition cylinder from On to OFF five times.
4. Open and close the “driver side” door 6 times.
5. Remove the Master Key and insert the new duplicates key.
6. TURN THE IGNITION CYLINDER ON.
7. The new key will be registered after 60 seconds. The THEFT light on the dashboard will go out, indicating that programming has been
to make your lexus remember your key's wireless signal:
For the remote part. in drivers seat WITH DOOR OPEN. start with door unlocked. first put master key in ignition, turn to on, then back off and remove. using the lock/unlock button on drivers door. press lock.. then unlock 5 times.(lock,unlock,lock,unlock,lock,unlock,lock,un lock,lock,unlock)
Close drivers door, open drivers door.
Performe lock/unlock procedure again. DO NOT close and open drivers door. Just the lock/unlock procedure again.
insert NEW key in to ignition and turn to on, then back off and remove.(at this point the doors should lock and unlock by themselves ONCE)
Now press both lock and unlock buttons on REMOTE. release after about 1.5seconds. now press just the lock button on remote. once you press the lock button, the car should lock and unlock ONCE, if it lock unlocked TWICE you messed up somewhere.
now open and close the drivers door a couple times to close programming. if you did it right, remote will now work.
thats it..not to hard once youve done it a few times
I tried this for about 40 minutes and finally my is200 remembers all my keys now.