It can be done. Your dealer might not be willing to deal with the hassle.
Here is the basic list of what can be done:
Operation Verification Beeper Volume (93%/89%/89%/75%/50%) [default=84%]
Door Ajar Warning Beeper (off/on) [on]
Time Until the Operation of the Autolock Function (30/60 seconds) [30 seconds]
All Doors Unlock when pressing unlock switch twice (off/on) [on]
Interior Light Function (off/on) [on]
Panic Alarm Operation (off/on) [on]
All Doors Unlock when key operated twice (off/on) [on]
Interior lights illuminate when the doors are unlock by the door key (off/on) [on]
Interior light illumination time (7.5/15/30seconds) [15 seconds]
Headlight Illumination time (off/30/60/90 seconds) [30 seconds]
Auto headlight on sensititity (dark2/dark1/normal/light1/light2) [normal]
Automatic light control mode (old/current) [current] (???)
Air conditioning startup mode (recirc/fresh)
Defrost startup mode (recirc/fresh)
Air Conditioning Tempshift (unsure of settings)
Defrost link (unsure of settings)
(the last few were hand scribbled notes added on so I don't have all the setting
Note - the GS, LS, ES and other Lexus models have more CBEST options than the IS300...
thanks for the replies guys.
Teg...I read your original post and that's how I knew about CBEST. thanks for the info.
Lexarkana...which dealership did you go to to change your beep volume and how far is that from Manhattan?