Debugging PO wiring hack-job
76 F250 390 Manual-4spd SuperCab.
It used to have a dual battery setup. half of the parts including the battery were removed before I purchased. Now I have a few wires I'm trying to reroute.
There is a set (1 blk w/ 20GA fuseable link, 1 red w/ 16GA fusable link) that have a common ring terminal. Looks like it used to run to the secondary battery, but could go to the main. THIS IS A STOCK WIRE. it runs through the firewall... connects to a square flasher unit thingy and back out the firewall into a large wiring loom.
What is it? why did the truck run fine without it? I think it should be attached to the main battery... not sure.


