Toyota 2011 Avalon Quick Reference Manual page 517

n Stopping the engine
Shift the shift lever to "P" and press the "ENGINE START STOP" switch as
you normally do when stopping the engine.
Replacing the key battery
n
As the above procedure is the temporary measure, it is recommended that
the electronic key battery be replaced immediately when the battery
depletes. (→P. 428)
AVALON_U (OM41428U)
5-2. Steps to take in an emergency
I n f o r ma t i o n P r o v i d e d b y :
5
495