My harness behind the dash is all chopped up and rigged up poorly and I'm tired of tryin to figure out why my gauge cluster lights don't work. How hard is it to remove the harness so I can replace it with one not so chopped up? Do I have to be year and model specific when I go to the yard to look for one? My truck is a 79 F250 4x4 thanks in advance for the help guys!

 

It would have to come from a '78 or '79.

 

Also it is my understanding that if you have gauges (oil press and alt) instead of idiot lights, you will need a harness from the same setup and vice versa.

 

Yes keep it the same like the first two post said. It's not to hard, I would label a few of them if they look anything like another one just in case.

 

Where are all the plugs at besides the obvious ones. Like where does the harness start and end?

 

There is only connection you need to worry about

The 18 pin connector is what makes it work.

18 pin connector for gauge
14 pin connector for warning lights

You can use the cluster from an 80's E-series Van with gauges
The cluster back is made of plastic

or you can try and find one on ebay

 

I got my harness out of the yard today had to take a chance tho none of the trucks had a cluster to see if it had idiot lights or gauges. I pulled the harness from a 78 F150 sc with ac they look the same as far as connectors go hopfully ill get it in today!!

 

I replaced the harness and I still have the same problem I even changed the cluster because the red plastic stuff on the back of the one that was in the truck was burnt in one spot! Is there anywhere else these lights tie in at that would be causin me problems I'm back to square one now.

 

They tie in through those copper strips.

So you took a complete harness out of your truck and put in another harness from a 78 and used the cluster from that other truck and you still have cluster lighting problems ?

How is the fuse ?

 

Fuse looks to be good its half blue at the bottom so I don't know if its broke below that point.

 

I was going through similar problems, as well as having a ton of burned, cracked and broken wires all over the truck. Rather than put a bandaid on the harness by fixing the few I could find (and still having 30 year old junk wiring) I bought one of those universal harnesses off ebay and am starting to rewire the whole truck. Took about an hour and a half to remove and label the entire old harness. The new harness comes with blade fuses and each wire is labeled every 5 inches or so along the whole line. I also ditched the control module and regular distributor + coil, and went with an HEI with one wire. That way I can remove more wires as well as a setup I know to fail often.

 

You can't sight test a fuse.

You have to use a multimeter and check for continuity.