Having some kinda weird electrical issue with my 07 F250 Super Duty 6.0L PowerStroke. When I put the key in the ignition and turn it to RUN the entire electrical system starts freaking out turning on and off and the lights start flickering on and off etc. I can also hear relays that are under the dash and under the hood in the fuse compartments rapidly clicking on and off. This is all happening with just the key in run, then if I try to start it it just clicks like there is no juice in the batteries but both batteries are fine. Once I turn the key to off then everything goes back to normal.

Here is a video I took that should hopefully explain things a little better. I shot it real late tonight so everything is really dark but you should get the point. Basically I turn the key to RUN and leave it sit there and everything is just flickering on and off. Then I try to start it and it just clicks rapidly like when your battery is dead. I turn the key to OFF and the dome lights and everything else goes back to normal. The headlights are bright as hell, the alarm still works, if I turn the key backwards to ACCESSORY mode my radio and everything else works etc.

CLICK HERE FOR VIDEO!!

I have checked every damn fuse that is under the dash and under the hood. Didn't find anything blown. I also pulled the 601 circuit breaker which didn't change things either. I am not sure what else I can check to fix the issue...?

 

Bad battery, bad battery ground, bad battery cable, bad battery cable connection, etc.

You have a fault in the primary electrical power system, ie, related to the battery and its feed to the rest of the vehicle.

Start by having the battery(ies) load tested outside of the vehicle.

 

Went and had the batteries load tested and it turns out that they were both bad. New batteries solved the issues! Thanks guys!

 

This thread was throughly discussed in the 6.0 diesel area... search for it if you need the info.

 

definately looks like a bad/ loose/ corroded connection somewhere. Best to discuss this in the diesel section, get some really good resposes..

 

Uh, he already replaced the batteries and fixed it....

 

I apologize about that. It was late, and I read that wrong.