Lexus 2012 RX450h Owner's Manual page 902

5-2. Steps to take in an emergency
Taking out the spare tire
Lift up the deck board. (See "Taking out the jack" for details.)
STEP 1
Remove the spare tire cover.
STEP 2
Loosen the center fastener that secures the spare tire.
STEP 3
Vehicles with a compact spare tire
Vehicles with a full-size spare tire
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