I lost the only key to my 1999 LS400 last night. My car is effectively completely inoperable now. I still have the shell of a key with the metal key part but I no longer have a radio (the part with the keyless entry buttons on it, plus the chip which is required to start the car). What is the most inexpensive yet correct way of getting another key + radio paired to my car?

Thanks in advance.

Not a good situation. A new ECU may be in order -- although the following thread is for a GS I recall the LS being the same.

https://www.clublexus.com/forums/gs-...-all-keys.html

Couldn't a dealer with the s/n of the car make another key programmed from a blank one? BMW does it without any issues. Only problem is they charge like ~500.00.

I just had to have a locksmith reflash my computer and cut two keys programming and programming the remote. All in $700. Cheaper than the lexus dealer option by half. Programmed two master keys and the valet. Didn't have to redo the locks as the master key I had had no guts or chip to start the car.

I'm curious how he reflashed it. Did he remove it and crack it open? I don't believe the 98-00 ECM is designed to be reflashable, at least thru the CAN bus. That's why the dealer will only replace it on 2nd gens.

With a proper tool, any thing can be done to ECU thru OBD II port .

Not sure about using the ODBII port on an LS400 for flashing. LS430's and other newer models don't have this limitation. This locksmith needs the ECU out of the car:

http://mcguirelocksmith.com/locksmit...shing-service/

LOST MY ONLY KEY..... that is the worst statement anyone could make that has owned a car for over a few days....
your key shell should have numbers on it like HYQ1512V.. this will help you..

lexus has a program whare they will give you a free ecu out of goodwill and 2 sets of keys, you just pay for the labor, do a search. others have had success with it.

I have and 01 GS 300 and they removed the ECU. Reflashed and then reinstalled it In the car. From what I can understand it cannot be done thru the OBDII port.

Any thoughts on this video? This guy is showing how you can pair a new key with the car as long as you still have a master key. I still have a master key, just not the wireless module that sits in it. This guy's master key appears to be missing the wireless module as well.

The wireless module is the part that has the chip in it, at least on a 1998. I know it because mine fell out and I couldn't start the car until I held it close to the key. Without the chip, the ECU has no idea if the key is master.

https://www.clublexus.com/forums/ls-...mmed-keys.html
Here is something I found a long time ago.

That video is perfect. I'm going to try that this weekend with a friend that is very skilled working with ECUs.

Well if the car will start with the master without the remote guts then the chip is still in it and it can program a new key. All I had was the key no chip no program. It would not start the car but would open doors and such. I had the valet key but you could not program a new master with the valet key.