My cluster started to flicker and dance like one of those music driven light apps.
Being my 4th 6.0, this is my third time going through this. So I promptly ordered a new one through circuit board medics.
Their tech support is good, but the time zone difference is a real pain in the ***, since I can troubleshoot anything until after work.
New cluster shows up, and it has no illumination. Everything functions, but it won't light up.
Tech support gave me a list of fuses to check. All are good. Pulled each one and checked continuity with multimeter.
I put the old cluster back in just for sanity test, and now it is blacked out as well.
Then I noticed my fog lights are no longer turning on. Checked the fuse on those, it's good too.

Contacted tech again, they gave me a list of pins to check for voltage.
All checked out at 12.xx but two, which were less than 5v. But both those pins (black plug) seem to just have loose holes. I was using a pin from my welder pick set....so I'm not sure those are giving a good reading, even though I do have a quality meter.

Won't lie, I'm terrified to take that black plug apart, brittle plastic... But I think I need to get in there to be sure I'm getting a solid connection for reading. I'm going to the junk yard in the morning in hopes of finding a superduty that I can grab an extra set of black/green plugs, incase I break something.
I traced wires back in the dash as far as I could, and saw zero chaffing or any other indication of shorting out or anything.

My headlight switch does seem to be a little worse for the wear. So I did order a new one tonight. Regardless of the issue, I have been wanting to get a new one anyway, so that is done.
Could the switch be causing the no light up? No fogs?

I sifted through the tech folder (awesome!!) But didn't get me anywhere. Been looking on line... Searched here, didn't find anything different. Most information says, 'yes, they go bad, get them replaced." lol.
Been troubleshooting this for three days now.
Anyone have any further advice?
Thx.

 

Man, this unicorn is beyond pissin me off.
I don't drive my truck much, but last night had to go rescue my son. Turns out that in addition to this mess, my tail lights also stopped working. Being summer time, I haven't driven this truck in the dark much, and not at all since replacing the cluster and having problems. So now the pressure is on.

I did find some information about the main fuse box under the dash can go bad. I hate throwing parts at an issue, but I'm about to.
I traced the wires back from the top cluster harnesses, as far as I can reach, and they look good so far.
I would think that beyond that, they would be connected to the dash frame, and not much chance at chafing.

Even though no one is chiming in with any additional ideas, gonna keep this going so when I finally do figure it out...maybe it will help someone else.

 

What plug are you thinking of taking apart?
Did you back probe when checking the pins for voltage?
Do you see moisture in/on the Central Junction Box under the dash?
Has the windshield been changed out recently (more of a 7.3L issue, but it can be a problem)?

 

First ...answering questions. Thanks for posting up Bismic.

I haven't taken any plug apart yet. But was planning on taking the main black and green harness plugs for the cluster apart and checking. Reason? The pin holes are so tiny, I only found one object that was the right size to stick in the holes and check voltage. But I'm afraid it's too small, and I'm not getting good connection.
You can't back probe the pins without poking into the wire sheeth...which I'm not a fan of doing.

I haven't seen any moisture in or on the central box under the dash...but I have not taken it out yet...so no promises.
Have not had the windshield replaced since owning the truck.


Update: I did find that my fog light fuse had blown, SINCE my initial testing....so that tells me that I lost my tail lights after doing all that before.
Fogs and tail lights are on same circuit aparently. Odd....but ok. So now I'm back to square one with just not having any cluster or dash lights (switch and controls).

 

You can do this without piecing the insulation: