I have a 2007 f150 4.6 liter. I have just replaced the starter along with cleaning the battery terminals and checked the battery and wires to the starter to verify a good connection. Once replacing the starter the truck cranked 4-5 times back to back with no issue. I stepped away for about 15 minutes to try to start it again and nothing happened. Not even a click. Did some troubleshooting and discovered that I can go under the truck and cross the solenoid and it will turn fine. I get nothing from turning the key. I traced the yellow wire from the solenoid on starter back up to beside the battery to a plug that looks like the inline fuse. I unplugged that wire and straight wired the yellow wire that goes to the solenoid and it starts fine. But this plug that's next to the battery that contains the yellow wire will not work while turning the key. I have also changed the starter relay the ignition feed and starter solenoid feed in the right kick panel. What have I missed? What role does this yellow wire play? What else can I try? Any help would be very appreciated.

 

do you have continuity thru the yellow wire?

 

I'm not really mechanically inclined sorry lol, but I do know the part coming from the solenoid has fire. The side from the battery has none. There's what looks to be a harness u can unplug before the battery. Inline fuse I think.

 

I have to knock out for the night but thanks ahead of time to anybody who offers any kind of help this truck is giving me grey hair

 

Need a multimeter to troubleshoot..

 

To troubleshoot what? I'm not sure what else to look at?

 

Does the theft light blink really fast?
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I figured it out! The theft light was blinking. The key i was using was a spare. I originally got the truck from my grandpa. I had him bring the original key, i turned it to on, it cleared the light and cranked immediately. Wow, why did this happen?

 

Spare key need's re-programmed.. glad you got her going.

 

PATS (passive anti theft system) keys have computer chips in them, non programmed or non PATS keys can only actuate the mechanical part of the lock. Sometimes that chip goes bad.
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