Lost my only master key. Helpppp!!!
 

My key case was broken and apparently the actual transponder inside the case fell out and of course you can't start the car without it because of the immobilizer feature. I only have a valet key to start the car right now but I want another key with the remote and transponder but I heard its a lot more to it then just buying a key off of amazon or eBay, and programming it to the car. Can anyone please help?

I recall you do need a master key to program the immobilizer for another master.

But I thought there were tricks around it, maybe techstream? or Immobilizer resetting?

Speedkar9 can chime in.

I have a toyota smart key maker that I've used on an 04 RX, didn't work on my 2000 ES, did the foot dance trick for that but did require me to use a master key.

If not then the dealer would be the only other way...

Same thing happened to me, really crappy and thin plastic on the key. I was able to get it done locally for about 75, but the key did not have the remote unlock feature and I did not need it as it was only a second key. Call around and ebay is your friend.

If you don't have the black key with the buttons, i think you are out of luck unless you reprogram the entire system by the lexus dealer

What year? My '02 has an emergency transponder and spare key for this.

2005 es 330 where is it located

I bought mine used, but it is a plastic card with a key and a RFID chip that you put close to the key to activate it. Maybe someone else can chime in. What does Lexus want to make a new key from your VIN #? I'm sure a small fortune!

Search Ebay for lexus ecu reflash

You can reset your ECU to a virginized state to accept new master keys.

Master keys can be purchased on eBay. I recommend getting one with OEM guts because the electronics are better than the replica stuff, I've had a bad experience with mine.

Here's the video:


Here's the writeup:

https://www.clublexus.com/forums/es-...apped-ecu.html

Now the programming procedure will be a tad different on the 4ES since it most likely uses a separate transponder ECU instead of storing keys in the ECU itself. Once you virginize the EEPRROM and reconnect it, you'll have a handshake procedure to perform so the ECU can talk to the transponder ECU before starting the car. Good luck in getting at the transponder ECU, its buried way under the dash somewhere.

Here's where its located on the 2RX:


If you simply need to add keys and have a master chip already, you have to do so with techstream: