Sometimes not all the times you can fix the FICM. You can check it if you have a voltmeter, theres a lil cap on top with two screws. You will see either 4 or 7 bolts. You want to test the one closes to the fender, have someone crank it but not start it. It should read around 48 volts.

Was the truck warm when you had these problems? You can always plug the block heater on and after it warms up try to see if it fires up.