i have a 2003 trailblazer it wont start changed the fuel pump that was not it still wont start

Make sure battery has a full charge and connections all good. Engine cranking do you have spark at the plugs and fuel injector pulse? If the answer is no, check for rpm signal, comes from crank sensor. Don't replace anything unless your testing points in that direction. I did look at your security system, it said passlock, that usually only disables the fuel injectors, if security system is involved.