Essentially the car is in front wheel drive until the computer detects "slippage" then it passes some of the traction to the rear. It does this all by itself without human intervention. Clicking the 4WD lock engages all wheels to a point to get you out of a rut/snow bank/etc. This is NOT a full time four wheel drive system like offered in a Jeep.. Currently have two F250 4x4s too. The RAV gets the mileage of any other brand's front wheel drive because that's what it's in most of the time. But it doesn't react to the front drive slipping to engage the rear differential clutch, it ANTICIPATES slippage using it's accelerometers.
Greetings on your new vehicle! A 2020 Toyota RAV4 doesn't have a unique button you have to press to engage four-wheel drive. The all-wheel drive in the 2020 Toyota RAV4 is made to react to the state of the road. It will employ front-wheel drive to save gasoline when road conditions are ideal, switching back to all-wheel drive when necessary.. In the 4.4 RAV4 it got renamed to "Dynamic Torque Control" but it is the same system with the additional awareness of Sport mode, which was new on the 4.4 models. Under normal circumstances the 4WD RAV4 operates in front wheel drive mode for increased fuel efficiency, with the rear wheels getting some portion of power only when it is detected.