TLDR...Silver bullet fix: Check your TSB’S Not exactly a diagnostic video, more so a process video.
This Ford F150 gets towed in for a cranks and no start, once off of tow truck, vehicle fires right up with no hesitation. Next checked codes and found no codes in pcm. Next thing I wanted to verify fuel pressure and fuel pump amperage, the fuel pressure was within spec but the amperage was slightly low at 4-6 amps.
Next I checked TSB and found a relocation kit for the fuel pump fuse due to burning up. Grabbed the thermal imager and was able to see the heat/resistance. Pulled fuse and found it burnt like TSB mentioned. Which is exactly why it cranks but won't start, and exactly why we check TSB's.