I was installing the fuel pump wiring upgrade today and got finished, went to turn the key to turn the pump on and.....nothing. Checked the 86 pin of the original fuel pump relay, not even a twitch when the key is turned to run, and keep in mind it was working fine an hour before. I even tried starting it, and the starter didnt even think about moving. The battery has a full charge.

Tried hooking my laptop up but hptuners cant find the VCM so I cant connect.... All of the dash lights and stuff work fine, and no blinking lights either...

I pulled the tank down and hotwired the fuel pump via the new wires with a lawnmower battery and it works fine...

Dunno if this matters, but should front most post on the underhood fuse box get power in "run" or "accessory"? Because mine doesnt...

Really need help with this one....

 

Check the fuse for the post. I believe that post is hot at all times though.

 

It sounds like you've lost power to the pcm. Have you checked out your fuses?

 

Just posting this up for general knowledge. Actually, just me goofing off with Paint....

 

RE-Check all fuses underhood and in the instrument panel. Sounds like a blown fuse to me.

 

What it REALLY sounds like is your truck rejecting the whole 408 idea.... Better sell it to me, save yourself the trouble

 

The post on the right has 12v, but the post on the left does not have any. Where is the fuse for it...and more importantly any idea why it would have blown?

thanks for the help guys

 

It is shown as "Stud 1" in the diagram.

 

Could've blown while you were doing wiring, if the battery wasn't disconnected.

 

Got it. PCM B was blown....

thanks for the fast help guys