f150 wont start,wont crank

Make sure battery has a full charge and connections all good. Note the diagram for starter motor. The starter relay is in the fuse box. Yes, older ford vehicles used to have solenoid/relay on the fender lining or firewall, but, not this one. I need to add, my info says your security system will disable starter motor among other components. If security system is the issue, you may need a scanner to communicate with that system in order to fix. Any applicable trouble codes? It should be possible to bypass everything just to see if starter motor will crank the engine, just for testing. If you try that make sure transmission is in park or neutral and parking brake is set. Make sure vehicle can't move. Just my opinion.