Hi,

I have recently had a break in at my house and one of the four keys for my 2000 LS400 was taken. It was only one of the two valet/service keys so I was wondering if it is possible to remove that key's transponder code from the ECU so that even if they can still get into the car they cannot start it. Failing that I think I am going to have to start leaving my car at someone else's place!

Any help/suggestions would be greatly apreciated.

 

don't believe so, may be better off getting your own key reflashed but i forget how it works with the '98-00s

 

The attached document describes how to remove all previous key codes and add new ones on a U.S. specification 98-00 LS400 -- the procedure may or not be the same for Australia ... there are many differences in the Lexus cars sold around the world.

 

from reading that "reflashing" article, the key is not encoded with a code to start the car. that reflashing just chooses which keys can use the remote lock/unlock feature. so since they have a key, even if you disable the remote lock/unlock they can still start it. unfortunatly, it appears the car would have to be rekeyed to rectify this problem.

 

My vague recollection is that the ECU memory stores 5 keys. As new ones are added, the older ones are removed from memory. Theoretically, I would think the valet key can be removed but the other problem as you stated exists to gain entry to the car.

A re-key might be the better safety measure here.

 

That pdf is very interesting and might come in handy Jim, although I think I agree with williamb that is only for the entry and not immobilizer. I have asked Lexus if they can give any further information about the immobilizer and they seem keen to help, but quoted around au$5000 for new tumblers/keys/ecu. Maybe just superglue the locks and hope the wireless batteries never go flat.

 

I had this same problem in 2003 when one of the keys for my 2000 LS400 was "lost" for a few days. I was told by the local Lexus dealer that step #4 of the procedure I provided would remove all previously registered keys and that a previously registered key could not start my car after all keys were deleted and the keys I had in my possession were added back into the system. But ... again ... confirm this with your local Lexus dealer as systems in Lexus cars work differently in various world markets.

You and I have similar cars although the 2000 LS400's sold in Australia had a substantially higher level of standard equipment than the ones we got here in the U.S. They are nice cars but not worth much after 10-11 years. Assuming you have insurance that would cover theft of your car, maybe it would be good to not spend much emotional energy worrying about it getting it stolen. It's just a car. I still like my car a lot even after all these years but if mine was stolen tomorrow, I'd see it as an opportunity to buy something more interesting.

 

Too true, I had already been looking around at a few LS430's here. Unfortunately the LS never did as well in Aus as in the US and they are very thin on the ground. Also it seems that your car prices are unbelievably low, even taking exchange rates into account they seem to be about half!

 

damn.. that sucks man.