Can the gas tank cover cause the engine check light to come on on the 2005 Toyota Highlander?

Yes, a loose or damaged gas tank cover can cause the engine check light to illuminate on a 2005 Toyota Highlander. This occurs because modern vehicles have an evaporative emissions system that monitors the integrity of the fuel system. If the gas cap is not sealed properly, it can trigger a fault in this system, leading to the check engine light turning on. It's advisable to check the gas cap and ensure it’s tightened or replace it if necessary.