Ok 05 f250 will not start ficm power will go to 48 then drop logic power never reaches 12.0 volts stays around 2 or three. none of the interior lights work. last time the truck was operated the dash lights started flickering the radio said low power. I am assuming this is being caused by a bad connection or electric componet.

 

Starrt by checking the Batterys and Alternator and Battery Cables ALL Battery Cables follow the grounda to where they mount at Frame and Engine

Unhook the Alternator electrical connections see if the Power will jump back up to 12 volts range

A bad alt can short out inside and Drain all Power with Key on

a Fulley charged Battery should be at 12.68volts unhook all Battery cables and check each Batt separetly

 

tried unkooking the alt with no change all battery cables look good at connections has new set of bats and my 07 is currently hooked to it just to ensure good voltage.

 

so batterys are good when tested alone with a DVM

Will it even turn the starter??

 

think benny is calling it. low voltage.

 

found problem but first a little back story on truck. Original owner was princess cruise lines up here in fair banks. They keep every service record for a vehicle they opporate so I am currently looking at recipts for $60,000+ in repairs and maintnance. truck was eventualy retired and sold at auction second owner purchased truck drove for a few months then it gave him the things listed above with the dash lights and low power. A friend came to me a couple days ago and started asking me about the truck and if I thought it would be worth getting. I honestly figured it was just a bad ficm. So I told him to jump on it. Truck sat parked in the second owners yard for 6 months before we loaded it up and towed it to my place yesterday with my 250. Pulled ficm this morning (BTW do not recommend pulling a FICM at -40 outside). opend up resoldered connections and reenstalled still showed same voltage drop on scan guage. At this point i came to you guys and started checking the tech folder. Benny you were right it was a low poer issue to ficm caused by an improperly installed fuse under hood. Long story short bought unrunning truck for 3800. install fuse properly and now we have another 6.0 back on the road thanks to you guys.

 

well 3800 bucks is a Great Deal

IDK that I help to much Honestly

atleast it back ALIVE!!!