Truck won't start

[hc superduty]

So I have been driving my 02 F-350 4x4 7.3L for just ove a year now and out of nowhere the truck is having problems starting. On tuesday I go outside to go to work and when I go to start the truck sothing happens, not even a clicking noise like a dead battery. I figure that it is the starter so I take it off and go down to autozone to have it tested and it works just fine in the machine. bring it home put it back in and the truck starts right up. I shut it off and start it back up a few times and every time it fires up no problem so I take it to work, make a few stops and have no problems. That night I go outside to move my truck and again it wont start, now I'm pissed. The nest morning I go outside and give it one more try and it starts, so I take it straight to the dealership and drop it off. The next day they call me up and say there is nothing wring with it and I need to come pick it up. I go get it and of course it starts no problem. I bring it home and it works fine everytime I start it. Saturday morning I go to start it and it makes a ckick like a dead battery, so I test the battery and I've got 12 volts at each battery( and I did disconnect them from each other ) so now I'm guessing it has to be the alternator, unless anyone can give me any sort of suggestion. I would appreciate any help that I could get.

Also, I heard something yesterday about a low oil pressure sending unit that sometimes hangs up, has anyone else heard about this?

 

[JLDickmon]

honestly, it sounds like you have a bad battery cable
do you know how to do a voltage drop test, and do you have a good digital volt-ohm meter (DVOM?)

 

[hc superduty]

I dont know how to do a voltage drop test or even what that is. and also the voltage meter that i have is probably not very good seeing as i got it at harbor freight just so i could test my batteries.

 

[Tbar]

Starter relay............


Tbar

 

[JLDickmon]

Starter relay............


Tbar

I'd go for that..

 

[hc superduty]

thanks for the suggestion tommorrow I will try replacing the relay and see if that is the problem.

 

[hc superduty]

thanks for all the advice but now im tired of trying to fix it and im just gonna have it towed to the shop and hope they can figure it out.

 

[LOUIS2036]

Ck Power Going To The Starter When You Turn The Key To The Crank Position.if There Is No Power Your Fuse Box & Gem Module Inside The Truck Has Shorted Out From Water Contamination.water Leaks From The Top Of The Winshield Seam & Will Drip Water Onto The Fuse Box & As Time Goes By It Will Short Out.

 

[pollittax]

tis a very common thing,according to ford. we also had our crew towed last week , the dealer even stocks the fuse panel, 500$ later. good luck.

 

[hc superduty]

the only thing that makes me think that is not the problem is that the truck has not been wet for over two weeks, not even any condensation on the windows.