2013 Toyota Highlander Owners Manual - Page 474

1-7. Safety information STEP 2 Outer seat: Open the anchor bracket cover, latch the hook onto the anchor bracket and tighten the top tether strap. Center seat: Latch the hook onto the anchor bracket and tighten the top tether strap. Make sure the top tether strap is securely latched. STEP 3 Adjust the head restraint to the downmost position.