Andrew Fisher

First off, let me apologize if this is a repeat, I saw other threads but they all seem to stop after the battery or alternator. I have checked both of those and replaced the battery (didn't need too).

2005 F150 5.4 XLT

Last week I drove to my destination. turned my truck off and went inside for 3 minutes. Came back out to my truck and had zero power to my truck. After having my truck towed and doing some diagnostics I replaced the battery. The truck purred like a kitten until yesterday.

As I was driving back to my office from a meeting my truck lost all power to the dash, radio, ac, windows, etc.

Here is what I have done:
Battery-replace
Alternator- checked and is good
Serpentine Belt- Still there
Brake Fuses-good

Anyone have any suggestions?

Also, I can jump the truck but it will not shift out of park and it will stop running after 30-45 seconds.

techrep

iTrader: (1)

Voltage regulator in the Alt.. I know you said you had it tested but was it tested under load..

Andrew Fisher

Autozone hooked it up to their machine, which seemed to make it spin, I assume it was under load but am not sure.

techrep

iTrader: (1)

Nope !!

Andrew Fisher

I tested it under load below are my results. It seemed to pass under load as well.

Truck off: Battery 11.96 and up
Truck on: 14 and up
Truck, AC, Radio, Lights on: 13.86 and up

From what I understand truck on and acc. off it should be around 14.2 so that is a little low but Truck and acc on the truck shouldn't drop below 13 which it barely dropped below 14. These numbers confirm what Autozone said. The alternator seems to be good.

Any other ideas?

techrep

iTrader: (1)

Check wires for contact and ground... battery/alt/starter

Andrew Fisher

Will do, thank you.

techrep

iTrader: (1)

Yep... let us know