Saturday i go to pick my daughter up from a friends house. on the way i stop to get something to eat. When i come out , my 2012 f150 6.2 cranks but it will not start. It is dark and i have a pair of pliers. i disconnect battery (hey this seems to fix everything) nothing. after 15 minutes i sit in the truck i lock-unlock the doors a few times then the truck starts???? i get my daughter, drive home. turn it off and then it will not start. I get home at midnight and this is driving me crazy, i search for the fuse that runs the fuel pump. it is hard to get out and it is not blown but it is melted up one side. Next morning i get new fuse, problem solved.

why is this fuse melting, yet not blowing?

if your solution is that i should fill up at 1/2 a tank, save it, in the year 2012 this should not be an issue. If it is then ford should make any buyer aware that a 36 gallon tank is really a 18 gallon tank. the tank should have a recessed area where the pump sits so that it is always "wet" or the pump should shower itself with fuel to cool.

in a bad situation I ran it down to 30 miles to empty and it only held 32 gallons so i have a feeling they already fudged the guage a few gallon anyway.

 

any electrical connection that is loose will cause high amps/heat and melt the fuse, but not blow it. Make sure the pins that hold the fuse in the box are tightly holding it on both connectors.

 

Probably isn't an "18 gallon" issue, more of a constantly/consistently operating the vehicle with a low fuel level. You obviously know the cooling issue, so PWRA and deal with the consequences.
.

 

i fill up with 1/8 to 1/4 tank left all the time and have done this for 33 years, never had a problem.

what does PWRA mean?

 

ProceedWithRecklessAbandon
.

 

Replace the #8 relay inside the fuse box under the hood. In a pinch I have got two trucks (a 2013 8 cylinder and a 2012 eco boost) to start and run by just tapping on the #8 relay (fuel pump relay).

 

Hi
I have got one truck 2012 F150 6.2L .... I was going to home when the truck dead and It crank but no start. I have changed fuse 27 and relay 8 but unfortunatly the issue goes on ....i have also done the spark plug test and realized that there is no power hitting the spark plugs.....i do not know what todo and I need some advice relate to ....

 

check the codes

 

[SPOILER][/SPOILER
Hi Roadie,

Which codes ? Can you specify more ?

 

Plug a code reader into the OBD2 port.

 

hi

We plug a code reader into the OBD2 and the message was about "short circuit on the fuel pump" we have changed the fuel pump already but even though, there is no fire in the spark plug.

Maybe I have to look to the crank sensor .

 

What was the exact code? It's 5 digits that start with "P".

 

The programmer told me it was b10f1 ignition swich. probably this was the first error ....I will do it again tomorrow and let you know .

 

B codes are body codes, P codes are powertrain codes.

https://www.autocodes.com/b10f1.html

 

Tell me something in B codes , the car should start or I have to replace the ignition first ??? Or I need to check for P codes and clean them and try to start the car ?