Lexus GS300 1998 Owner's Manual page 285

STARTING AND DRIVING
" 1 "M" position
2 Downshifting on the front,
Upshifting on the rear
GS400: When the selector lever is put in the "M" position,
the "M" indicator is shown on the instrument cluster. Pushing
either of the switches on the front or rear of the steering wheel
downshifts the transmission from "D" to "2" position or
upshifts from "2" to "D" position.
The gear position being used is shown on the instrument
cluster.
Each time you push the switch located on the front of the
steering wheel, the transmission downshifts (from "D") to
"4", "3" and then "2".
When you push the switch located on the back of the steering
wheel, the transmission upshifts to "3", "4" and then "D".
For the precautions on each position, see the description on
the previous page.
272
2 warning tones sound in any of the following cases:
D You attempt to downshift the transmission when it is not
possible to downshift due to the high vehicle speed.
D You attempt to downshift from "2" position.
D You attempt to upshift from "D" position.
If the "M" indicator flashes, there is a problem somewhere
in the system. In this case, it should be noted that you
cannot downshift or upshift the transmission using the
switches on the steering wheel. Consult with your Lexus
dealer as soon as possible. The transmission works
exactly in the same way as when you put the selector lever
in the "D" position.