Lexus 2003 LS Owner's Manual page 235

(h) If the player malfunctions
If the player or another unit equipped with the player
malfunctions, your audio system will display one of the four
following error messages.
If "WAIT" appears on the display, it indicates that the inside
of the player unit may be too hot due to the very high ambient
temperature. Remove the disc from the player and allow the
player to cool down.
If "ERROR 1" appears on the display, it indicates that the
disc is dirty, damaged, or it was inserted upside down. Clean
the disc or insert it correctly.
If "ERROR 3" or "ERROR 4" appears on the display, it
indicates there is trouble inside the system. Eject the disc.
If the malfunction is not rectified, take your vehicle to your
Lexus dealer.
Rear controller (some models)
The rear controller is installed in the armrest of the rear
center seat so that you can operate the audio system in
the rear seat.
20L132c
"POWER" button: Use this button to turn the system on and
off.
"MODE" button: Use this button to change the mode. If a
tape or compact disc is not inserted, the "TAPE" or "CD" mode
is skipped.
You can lock the button operation. To activate the lock, push
and hold the "MODE" button until you hear a beep. "LOCK"
appears on the display. All the buttons in the rear controller are
inoperative. To cancel it, push and hold the "MODE" button
until you hear a beep again. You can use all the buttons.
"VOL" button: Use this button to adjust the volume.
AUDIO
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