Ok, so I lost my one and only master key. Finally broke down and ordered from www.lexus-parts.com (Sewell). They offered 2 new master keys, plus cutting the keys to my VIN, plus the little circuit board that slides into the 'ECU' in the trunk for $286.
Got the keys but they didn't fit. They were cut for the wrong VIN. No problem, Sewell Fed Ex'd me a replacement. Received not 2 but 3 Master Keys!
Found the Field Service Manual for the 93 (probably from Lexus Owners Club). In the Body Electrical System pdf, found the section for 'Wireless Door Lock System'.
Followed the instructions and, yes little girl there is a Santa, I have 3 working Master Keys!
I think the procedure is a little easier for the 94 than what I've read for some later model years. You simply replace the little circuit board in the trunk and do this:
Open the driver's door
Use the door lock in the door and 'lock unlock' 10 times within 30 seconds
Within 2 seconds mash the transponder button on the Master Key repeatedly for 10 seconds
Close the driver's door
Mash the transponder and the door should unlock.
There are additional troubleshooting steps in the FSM if this doesn't work for you but it worked for me. So nice to be able to wirelessly unlock all doors as well as open the truck without having to first open the car.
It's the simple things in life......
And major kudos to Sewell Lexus! You guys rock! I got 3 Master keys for apx $295! My local dealership quoted my over $500 for 2 Master keys.