Toyota RAV4 owners may wonder how to put their vehicles into all wheel drive (AWD). Some may also wonder what the “Lock” button on their dashboard does. Well, the “Lock” button is actually used to switch the RAV4 to all wheel drive. Here’s how it works.
Press the “Lock” button to enable AWD. The 
dash light will illuminate to indicate AWD is turned on. Press “Lock” again to turn it off.
Your vehicle must be traveling below 25 miles per hour. Otherwise the “Lock” button will not do anything when pressed. If you are using AWD below 25MPH, then exceed 25MPH, AWD will automatically be disabled.
When the RAV4 is in AWD mode, the rear wheels are engaged and more power is sent to all wheels. It should be used in instances when your vehicle is stuck in mud or snow.
Does the hybrid model have this feature
Does my rav4 2000 model support this LOCK function or not ?