It just happened today and thought maybe the cold weather had something to do with it. The battery works, and the gas is full. I even tried the security trick. Are there any other quick fixes I could do before letting a mechanic take over?
You have to check for spark and fuel pressure when the engine won’t fire up.
For a quick test for a lack of fuel pressure (or the lack of fuel) remove the air intake hose from the throttle body and spray a little starting fluid in while cranking the starter. (Unless you have reeeeeaaaaalllly long arms, you’ll need a helper to do this.
If it fires up, then quits immediately, you have a fuel supply problem.
You might borrow a scan tool at the auto parts store and read the code(s). Sometimes you get lucky and solve the problem with no previous experience.