I have to share my frustrations and experience with replacing a key. I went swimming with a key in my pocket. I found it at the bottom of the pool after 30 minutes. Dried it out thoroughly, but it was possessed. The key would randomly actuate the “unlock” button, and the car would obediently open all the windows and sunroof, and beep. It would do this in the middle of the night. So that key is dead. The key would continue to start the car, so I removed the battery (disabling all the remote functions) and used it as a dumb ignition key for a while.

I ordered a replacement cheapo key from ebay. I tried following the gas-pedal-five-times, brake-pedal-six-times program method with no success. I tried the “add a key” option with my copy of techstream, also no success. However somewhere in the process it UNREGISTERED my dumb key - so it would no longer start the car! Off to the Lexus dealer who charged me $110 to try to register the ebay key, and re-register my dumb key. Apparently you MUST have a battery installed in the key module to successfully register the chip with the immobilizer.

Next I tried an Amazon cheapo key. It worked perfectly. I registered the key to the immobilized using techstream with no problems. I used the remote remote.com instructions to program all the remote functions, with a few hiccups. The instructions are written in such shorthand, they omit some critical comments.

So my offering to the forum, is the same instructions with my comments ADDED IN CAPS.
One gripe - The clublexus forum search functions are frustrating, can’t find threads I know exist. Multiple word searches didn’t work for me.

I kept my old swimming pool key, and just popped the new module from the Amazon key into the old shell. (And threw away the new amazon blank key and shell) That works fine.

Remote Programming Instructions:
1. Begin with the key out of the ignition.
LOCK ALL THE DOORS, THEN
2. OPEN the DRIVER'S side door ONLY AND LEAVE IT OPEN! LEAVE all other doors including the trunk CLOSED.
3. Within 5 seconds INSERT the key into the ignition and PULL it out TWICE.
4. CLOSE then OPEN the DRIVER's side door TWICE, AND LEAVE IT OPEN.
5. Insert key INTO the ignition then REMOVE it.
6. CLOSE then OPEN the DRIVER's side door TWICE, AND LEAVE IT OPEN.
7. Insert the key INTO the ignition and LEAVE it in ignition. DO NOT TURN IGNITION ON.
8. CLOSE the DRIVER's side door.
9. Switch the ignition to ON then OFF.
10. REMOVE the key from ignition.
11. The door locks will now cycle to confirm the vehicle has successfully entered programming mode.
12. PUSH and HOLD the LOCK and UNLOCK buttons SUMULTANEOUSLY for 1.5 seconds on the NEW remote being
programmed. As soon as you let go, press the LOCK button ONLY, and HOLD it for 2 seconds.
13. The door locks will cycle to confirm successful programming of the remote. If you have any
additional remotes to program repeat step 12 if you have no additional remotes proceed to step 14.
14. OPEN the DRIVER'S side door. Programming is now complete.