bobbyhIII

One key works to start the car but other key won't. Is there a chip or something in the key that one key would have but the other doesn't?

hankinid

Both keys should have chips that talk to the engine immobilizer ecu behind the dash. Did the one stop working all of a sudden, or is the '02 a new truck to you??

DrHess

You have to train the truck to the key, and there are two parts to it. One is to train the remote features, like door unlock and the other is to train the immobilizer. It is a rather complicated dance, unless you have the software/interface.

This works on a '98:
https://www.clublexus.com/forums/lx-...-98-lx470.html

hankinid

This categorically will NOT work on an '01...not criticizing, just noting that key dupe procedures seem to change like the phases of the moon with Toyota. On the '01, iirc, you insert your working master key in the lock and press the brake pedal, again iirc, 5 times within 30 seconds. The security light goes off, you remove the master, insert the new key, and repeat the process. Again, I did this a year ago and crs can strike at any time.

OP, I'd do a search for 'key programming' on ih8mud.com in the 100 series forum. Well worth signing up if you already haven't.

hth

Steve