How to Read Wiring Diagram
09-05-2017, 10:18 PM
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How to Read Wiring Diagram
Hello, I've got a 1975 F150 Ranger XLT that I am currently trying to rewire. Previous owners had such a mess of wires and many wires partially connected or not connected at either end 
, I didn't want to leave it. I'm just having a tough time reading this wiring diagram properly. I've got the Haynes repair manual for my truck, and it has a good diagram in it, besides the fact that all the plugs are shown as if they were vertical plugs. So when trying to wire the ignition switch for instance, the plug itself isn't like it's pictured. I just want to know how I can tell which wire goes where. Is there just a little trick that I don't know? Or is it going to be one of those you wouldn't know unless you already know type things? Pictures to demonstrate what I mean.
, I didn't want to leave it. I'm just having a tough time reading this wiring diagram properly. I've got the Haynes repair manual for my truck, and it has a good diagram in it, besides the fact that all the plugs are shown as if they were vertical plugs. So when trying to wire the ignition switch for instance, the plug itself isn't like it's pictured. I just want to know how I can tell which wire goes where. Is there just a little trick that I don't know? Or is it going to be one of those you wouldn't know unless you already know type things? Pictures to demonstrate what I mean.
10-11-2017, 04:10 PM
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Attachment 534987
Try this one, same as my '78
Try this one, same as my '78
10-12-2017, 08:07 AM
#4
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Reading diagram
Each block (straight plugs) is a connector of wires going to various areas.
Take the fuse block (lower left) then pick a wire to follow, any wire... and see where it goes/connects to. If you took the Haz/Stop wire and followed it you would see a black dot along the way.. thats a connection piont (wire) taking you to another point, in this case one to STOP LIGHT the other to HAZARD LIGHT.
the marking along various wires is the color of wire, some are solid in color others are multi (striped BLK/BLU going to dome light for example) each wire tells you where its going to from the different terminal blocks. One is connected to the back of your instrument cluster, squeeze the sides a d wiggle it out, another is connected to the steering column and so on. Individual wires are just connectors and are sometimes and mostly always difficult to seperate, examine closely and proceed carefully. I use a real small screwdriver to lift or depress the tabs.
If your really getting into it, remove the dssh cluster and radio/defroster assembly and you'll find it much easier to navigate in there rather than laying on floor looking up. I just completed a similar task and thats what i found easier. Just be careful with the dash cluster, its a thin plastic printed circuit board. Dont forget to disconnect the speedometer cable from the cluster to completely remove it.
Good Luck! You'll do fine just be "patient"
Take the fuse block (lower left) then pick a wire to follow, any wire... and see where it goes/connects to. If you took the Haz/Stop wire and followed it you would see a black dot along the way.. thats a connection piont (wire) taking you to another point, in this case one to STOP LIGHT the other to HAZARD LIGHT.
the marking along various wires is the color of wire, some are solid in color others are multi (striped BLK/BLU going to dome light for example) each wire tells you where its going to from the different terminal blocks. One is connected to the back of your instrument cluster, squeeze the sides a d wiggle it out, another is connected to the steering column and so on. Individual wires are just connectors and are sometimes and mostly always difficult to seperate, examine closely and proceed carefully. I use a real small screwdriver to lift or depress the tabs.
If your really getting into it, remove the dssh cluster and radio/defroster assembly and you'll find it much easier to navigate in there rather than laying on floor looking up. I just completed a similar task and thats what i found easier. Just be careful with the dash cluster, its a thin plastic printed circuit board. Dont forget to disconnect the speedometer cable from the cluster to completely remove it.
Good Luck! You'll do fine just be "patient"
10-12-2017, 03:17 PM
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Each block (straight plugs) is a connector of wires going to various areas.
Take the fuse block (lower left) then pick a wire to follow, any wire... and see where it goes/connects to. If you took the Haz/Stop wire and followed it you would see a black dot along the way.. thats a connection piont (wire) taking you to another point, in this case one to STOP LIGHT the other to HAZARD LIGHT.
the marking along various wires is the color of wire, some are solid in color others are multi (striped BLK/BLU going to dome light for example) each wire tells you where its going to from the different terminal blocks. One is connected to the back of your instrument cluster, squeeze the sides a d wiggle it out, another is connected to the steering column and so on. Individual wires are just connectors and are sometimes and mostly always difficult to seperate, examine closely and proceed carefully. I use a real small screwdriver to lift or depress the tabs.
If your really getting into it, remove the dssh cluster and radio/defroster assembly and you'll find it much easier to navigate in there rather than laying on floor looking up. I just completed a similar task and thats what i found easier. Just be careful with the dash cluster, its a thin plastic printed circuit board. Dont forget to disconnect the speedometer cable from the cluster to completely remove it.
Good Luck! You'll do fine just be "patient"
Take the fuse block (lower left) then pick a wire to follow, any wire... and see where it goes/connects to. If you took the Haz/Stop wire and followed it you would see a black dot along the way.. thats a connection piont (wire) taking you to another point, in this case one to STOP LIGHT the other to HAZARD LIGHT.
the marking along various wires is the color of wire, some are solid in color others are multi (striped BLK/BLU going to dome light for example) each wire tells you where its going to from the different terminal blocks. One is connected to the back of your instrument cluster, squeeze the sides a d wiggle it out, another is connected to the steering column and so on. Individual wires are just connectors and are sometimes and mostly always difficult to seperate, examine closely and proceed carefully. I use a real small screwdriver to lift or depress the tabs.
If your really getting into it, remove the dssh cluster and radio/defroster assembly and you'll find it much easier to navigate in there rather than laying on floor looking up. I just completed a similar task and thats what i found easier. Just be careful with the dash cluster, its a thin plastic printed circuit board. Dont forget to disconnect the speedometer cable from the cluster to completely remove it.
Good Luck! You'll do fine just be "patient"
Maybe I didn't make it clear. Non of the wires are still in the truck, and all the plugs are sitting in a box. There is absolutely no way for me to follow the colored wires to see which pin they go to. That's the ENTIRE point of getting a wiring diagram. If all I needed to do was follow the wires while it is in the truck, there would be NO reason for the diagram. So as far as I can tell, this diagram fails at its most important job. Great, it shows me that a wire goes from this plug to this plug, but which PIN does that wire go to on each plug?
10-13-2017, 09:27 AM
#6
Senior Member
I would say that the diagram represents and indicates each wire block as to how its wired even though its not an exact pic of it, the wiring to it is.
Sounds like you need the blocks as well, be prepared, restoration isn't cheap nor is fishing or vacations,, its the end result that matters to some. However, its cheaper than a new F150 plus you can generally fix/repair non computerized beasts... its all a matter of how you see it.
More people will notice a nice 70s F series than a new one. I currently have about 25-3000 into mine not counting the truck itself that i could have easily sold for 2500. before starting the frame off restoration and doing it myself.
So to me having a completely updated, sound deadened LED light foe a 6-7k total investment into a real clean 78' is worth it.
Plus i can fix it if need be.
Your options seem to be.
1. Go and find a junk yard for a complete harness and all necessary pieces you'll need.
2. Find a donor truck to rob from.
3. Contact "painlessperformance.com" for a harness for your needs.
Good Luck whatever route you go.
Remember, patience + satisfaction = lookers and a happy 70s F series owner.
Here is mine just before the teardown Jan.4, 2017
Sounds like you need the blocks as well, be prepared, restoration isn't cheap nor is fishing or vacations,, its the end result that matters to some. However, its cheaper than a new F150 plus you can generally fix/repair non computerized beasts... its all a matter of how you see it.
More people will notice a nice 70s F series than a new one. I currently have about 25-3000 into mine not counting the truck itself that i could have easily sold for 2500. before starting the frame off restoration and doing it myself.
So to me having a completely updated, sound deadened LED light foe a 6-7k total investment into a real clean 78' is worth it.
Plus i can fix it if need be.
Your options seem to be.
1. Go and find a junk yard for a complete harness and all necessary pieces you'll need.
2. Find a donor truck to rob from.
3. Contact "painlessperformance.com" for a harness for your needs.
Good Luck whatever route you go.
Remember, patience + satisfaction = lookers and a happy 70s F series owner.
Here is mine just before the teardown Jan.4, 2017
