I have several wires under the dash that aren't connected to anything, hoping someone can tell me what they are supposed to be plugged into.






1. black/yellow stripe wire, yellow 3-prong female connector. What is it for?



2. Just below and to the left of the yellow connector, black female connector 2 black wires going into it









3. White/red stripe and black/yellow stripe to green connector. After green connector, blue/red stripe and black wire, both wires are cut. Black wire has molded rubber/plastic thing that the wire goes through in the upper right of picture. Black wire is ground, blue/red is key-on power. 99% sure this is for the radio but just want to check also what is the black rubber thing?








4. Green/yellow stripe to female bullet connector. A thicker green/yellow wire comes out of the lighter goes to another connector and this wire comes out of that. It is always-on power. Are these wires for options I don't have?

 

idk what to tel ya murf unless something isnt working i personaly wouldnt worry about it unless it make ya loose sleep at night. ive got a bunch of that kinds "loose ends" on my truck but everything works........

 

1. is a keyed acc. feed there could be 1 or none going to this depending on what year you have
2. not sure don't see it on my 78'
3. your right on the radio- but yellow/black is + blue/red is the illumination + ground goes from radio to behind the istrument panel to a screw on the column support
4. would be a constant acc feed like cigarette lighter and glove box ill. or vanity mirror on visor on XLT

 

supercabfreak - yeah, I know. I'm not really worried about it, just curious. Previous owner(s) did a hack job all over this truck so just trying to figure out what's what. The radio that was in the truck wasn't hooked up so I'm going to put in a new one which is what started this. Also found a red wire that was just wrapped around other wires and not connected to anything on either end (pretty sure it was for a stereo that was added then taken out)

kingford72 - Thanks a lot
Do you have any idea what that black rubber thing is on the black wire for the radio?

FYI I have 77 f150 custom 2wd, no options except gauges instead of idiot lights

 

I can't see the black thing on the radio wire but it is probably a filter to help eliminate static from the charging system.

 

Unless you track down a wiring diagram for the truck, you are lost. Ford used one harness and extra wires and connectors are not uncommon, due to the varying options for a particular truck.