Before you do anything you need to inform us all of how you plan to go back in time to change the past.

Then, you should not do that and instead just try replacing the battery. Given that the transponder works for the ignition, I think this is your best approach.

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Tangent: Do the remote/keyless entry and the ignition security mechanism of the transponder work the same way? That is, if the battery is removed (or drained/dead) from the transponder, will the key still work with the ignition security mechanism to start the car? If not, then I'd put my money on the battery being dead. If it does, then I'd guess that the washing machine probably killed the remote/keyless entry.

 

Tangent: Do the remote/keyless entry and the ignition security mechanism of the transponder work the same way? That is, if the battery is removed (or drained/dead) from the transponder, will the key still work with the ignition security mechanism to start the car? If not, then I'd put my money on the battery being dead. If it does, then I'd guess that the washing machine probably killed the remote/keyless entry.

I've been wondering that too! My key is held together by glue so its a gamble to open it. Does the transponder need a power source in order to start the car? Can someone remove their key battery and try to start the car and tell me the result? Pls and thxs.

 

Go to eBay and get a replacement key from 1010keys for about $50.00 - they will 'cut' the key for you free if you send a photo of the key or the key number. . . .Excellent quality for the price.

 

He has an '01 and I think the key is married to the PCM..... He can't just get a new key cut and programmed IIRC

 

I believe the ignition security mechanism uses something akin to passive RFID, in that the ignition "powers" the "chip" as part of the protocol. That would imply that the transponder houses two separate circuits, one for the battery-powered long-range remote transmitter and one for the ignition security mechanism.

OP: I would first try a new battery, and if that fails, perhaps cleaning the circuitry inside the remote (assuming you can disassemble the thing without damaging it). Otherwise, you just need to get a new transponder, use the old one to program a new master with the new one, and then program the remote to work with the car (it's a separate programming procedure, as it's a different system).

 

Go into a dealership and ask them a couple questions about 01s and programming a new master key. Then showed them your mess :lol:

 

Well I perused the FAQ for the '01 key programming debacle. If your transponder is dead, then you are SOL

http://my.is/forums/f53/01-05-lexus-is300-key-remote-program-instructions-407990/

but you don't know its for certain dead.... so you could order a new key, but why do that. They key clearly works and starts the car. Its the transponder that is the problem.

But this guy says it can be done..... but if you read all 4 pages, it seems that the consensus is it can't be done.

http://my.is/forums/f53/01-05-lexus...1-05-lexus-is300-key-remote-program-instructions-407990/index2.html#post6678786

If you can find a new/used transponder cheap give it a shot......