Ford Repair Questions? Ask a Mechanic for Answers ASAP
The rule is that every time a fuse blows that was put there to protect a power/feed circuit, then that circuit is shorting to ground before getting to the intended load. Looking at the starting circuit diagram, we see that fuse F102 protects several electrical loads including the starter relay (which yo have replaced, so it should be good) and the ignition coils - one or more of these probably being the culprit.
The least complicated way to diagnose this issue would be to first put in a new fuse, then disconnect all 8 ignition coils. Next, turn the ignition switch very briefly to START. If the fuse does not blow, repeat the procedure connecting the coils one by one until you find the one(s) causing the fuse to blow. Once it is identified, make sure its connection and wiring are not chafed or rubbing against anything. Also make sure it's replacement meets the factory specs.
Please let me know what you find.
Almost forgot... Make sure to also check that condensation from the A/C plumbing is not falling on the coil connector.
There you go... that's probably where the whole issue started. Hope you find it soon.
That could very well be it - just test them as I suggested to make sure that is indeed the cause of the issue.
I won't be able to log back in until late tomorrow afternoon or evening. I'll opt out to let other experts pick this up. Please don't rate or reply until another expert responds or the site will cycle this chat back to me.
Welcome, I'm Chris (aka Moose) I prefer to work when others don't, I am here around lunch and after dinner till after midnight.
Would you like me to try and figure this out for you?
I am going to start over fresh so everything is on my mind what you and I have written. So I do not have to read what another wrote and make sense of it.
Does this fuse fail with the key in the accessory position, run position, or only while trying to start?
Since it only blows the fuse with the key held in the start position, that narrows it down to just one wire.
Do the next step using these 2 files.
Now hold the key in the start position and let me know if the fuse fails. If it does not fail, then reconnect 110 and unplug the TR sensor on the drivers side of the transmission https://dl.dropboxusercontent.com/u/90220402/DTR.png Now try to start it, does the fuse blow or not blow?