2012 Toyota Yaris Owners Manual - Page 463

1-7. Safety information Child restraint systems with a top tether strap Pull the head restraint up while pushing the lock release button. 1 Before driving Open the anchor bracket cover, latch the hook onto the anchor bracket and tighten the top tether strap. Make sure the top tether strap is securely latched. Push the head restraint down to the lock position.