Cranks, no start. wiring all messed up?

2006 FORD F-250
150,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
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RSFRANKLIN
bought with no starter. got starter - wiring all messed up. rewired both batteries, starter, alternator. still not turning over. changed relays and fuses, no change. changed coils and spark plugs, still no change. had one battery... got second - cranks a few times, no start. fuel pump engages. fuel filter, unsure... we think that maybe we dont have the starter, alternator and batteries connected in the correct order.

we cant find a definite wiring diagram online and Chiltons has us confused on locations!

the truck is gas powered. not sure if its 5.4l or 6.6l...

we have been at this dang super duty for almost 2 WEEKS! and YES. WE HAVE SEEN THIS TRUCK RUN... so we know the truck CAN START!

We will attach a video later today - we are just dang frustrated at this point!

any advice you may have, or directions you can give are greatly appreciated!

Thank you guys!
Dec 9, 2025 at 1:46 PM
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STRAILER
  • ✓ASE Certified Mechanic
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No problem, I can help you fix it. So to be clear the engine is cranking over (starter) or the engine is cranking over but not starting, please upload a video it will help us. It is probably a 5.4 liter engine btw. I could be the starter relay is not working but here are the wiring diagrams so you can double check the repairs to the starter harness. Also, please go over this video as well

https://www.youtube.com/watch?v=6YRW8fyNudY&t

Check out the images (below). Please let us know what happens.
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Dec 10, 2025 at 10:42 AM
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RSFRANKLIN
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Ok... This was a couple of days ago... We've since burned out the starter, and replaced it. The truck started with the new starter, we tried to drive it down the street, it stalled, wouldn't start again, killed the battery... We are just gonna leave it there for the night...

We will try again tomorrow... We appreciate any and all advice!
Dec 14, 2025 at 10:30 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,494 POSTS
  • ASE Certified Mechanic
It looks like you don't have a serpentine belt on the engine correct? if so do not drive the truck anymore until the belt is replaced. This will cause the engine to over heat and the battery not to charge. Thanks for the video it helps.
Dec 15, 2025 at 12:06 PM
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