Currently I have the original AM only radioin my truck. 1975 F-100 Custom

I have a Ford AM/FM radio that I would like to put into it but ran across wiring problems that are beyond my abilities

The wiring under the dash is very simple in the truck....

From a cluster of wires just behind the instrument panel is a two prong plug. Two blue with red stripe wires feed one prong, and a black with green dots wire feeds the other.

The plug from the radio in the truck only has two wires, one for each prong. The blue / red wire connects to a light mounted on top of the radio, and the black/green wire connects to the radio itself.

Speaker wires are simple, I understand where they go, just having problems knowing where the two (or three) wires are supposed to go in a newer radio. I have a 1992 ford radio, has 2 sets of pins, one is 8, one is 7. I found the wiring diagram for it as such (this is just the grey connector)

1. Amp
2. Power Antenna
3. Ground
4. Not Used
5. Dash Light Dimmer
6. +12 volt Ignition wire (blue w/ black stripe)
7. Not Used
8. +12 volt Battery wire (blue w/ red stripe)


I know i dont need half of them (the ones in red) And the ground is self describing.... if there was a clear ground wire in the truck.


So pretty much I have two (three if i seperate the two blue/red wires) to work with, and dont know which pins they should go to. I planned on making my own harness for this once I figured out where everything went.


1. Do I need to create a ground by running it from #3 pin to the frame?
2. which +12 volt power supply do i use, with which wires
3. Is this a lost cause and should I stick with the 1 AM station I get and listen to the farm report every day going to work



Thank you for your time, hope i didnt confuse too many people

 

Take a look at this post and see if it helps.

https://www.ford-trucks.com/forums/s...86&postcount=4

http://www.installdr.com/Harnesses/Ford-Wiring.pdf

 

Yea, that's the pdf I found for the harness diagram for the radio I want to put into my truck, but I'm still unsure what wires (existing in truck) I need to connect to what pins (in the newer unit)

Using the diagram in that link,

"K" is the ground
"N" is the +12 Volt Ignition Wire
"P" is the +12 Volt Battery Wire

But like i mentioned in my post, there are only three wires in the truck... Two go into one pin, and one in another pin.... The connector for the existing old radio only has two wires.... One going to the Light mounted on top of the unit (which I suspect also acts as a ground?) , and one going into the back of the unit.

One interesting thing I noted tonight. When I turn the ignition, the radio gets power, like normal... But the light does not come on unless I turn the headlights on..... And even with the ignition turned off, the radio light comes on when I turn the headlights on.


So would it be safe to guess:

"N" is the +12 Volt Ignition Wire (The single wire going into the back of the old radio)
"P" is the +12 Volt Battery Wire (The wire for the light mounted on top of the old radio)

But what is the ground if that is right? Should the two wires going into the same pin on the connector coming from the truck be seperated? Since they turn into one wire at the radio connector.....

 

If It were me, I would start fresh. Run a new 8-10ga wire from the battery for the constant power wire. Then find a switched power source that's pretty clean, it might be at the wires your looking at or you can try back at the switch. Then I would run a ground wire from the firewall to the radio.