Lexus GS 450h 2008 Owner's Manual page 535

To change the "POWER" switch modes: Within 10 seconds of the
STEP 3
buzzer sounding, release the brake pedal and press the
"POWER" switch. Modes can be changed each time the switch is
pressed. (
To start the hybrid system: Press the "POWER" switch within 10
seconds after the buzzer sounds, keeping the brake pedal
depressed.
If the "POWER" switch still cannot be operated, contact your Lexus
dealer.
Stopping the hybrid system
■
Shift the shift lever to "P" and press the "POWER" switch as you normally do when
stopping the hybrid system.
Replacing the key battery
■
As the above procedure is the temporary measure, it is recommended that the
electronic key battery be replaced immediately when the battery depletes.
(→P. 454)
P. 139)
→
5-2. Steps to take in an emergency
5
533