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Discussion Starter · #21 · (Edited)
I hope all is well. Question on Ignition wiring for the experts. My red and yellow wires look burnt
Electrical wiring Electronic engineering Electronic component Cable Electrical supply
. I just noticed this as I was working on my dash wiring. My question to the experts is… any idea why these would have burnt up?

I don’t know if this was like this before I bought it a few years ago or is this something I caused? Trying to understand it as I want to try and fix the root cause of the problem.

here is a picture
 

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I think that was there before you got it!!!
Looks like that is old solder on the wires from a repair attempt. And a poor job of soldering as the solder was not hot enough.

The yellow is power in from the starter relay, on the same lug at the battery + cable.
Red/Blue goes back to the starter relay and is hot when key is turned to start. Cross this wire with the yellow to crank the starter and you are half way to stealing a car!
Have no idea of the orange or red. That may power up some part of the fuse box

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Looks like you may want something like this

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Automotive tire Font Electric blue Gas Rectangle
 

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Discussion Starter · #24 ·
@Action your knowledge continues to impress the hell out of me :).
Schematic Font Parallel Technical drawing Rectangle
Thank you.

From what I understand ithe red wire goes to my coil and the “I” post on my starter relay.

I was trying to research and understand it too much power was going to these wires. So thanks for helping me!

One more question for you. From my understanding both the red-blue wire from the “S” on my starter relay and the red wire from the “I” on my relay connects to my ignition switch. Why two wires? Does the switch send power to the coil only after turning the ignition switch?

here is the wiring diagram.
 

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Red/Blue is only hot when key is move to start position. This sends 12V+ to starter relay "S" terminal to send power to engage the starter motor.
The "I" terminal is brown and sends 12v+ to a wire from the ignition switch down stream of a resistance wire. This supplies 12V+ to the coil ONLY during cranking. When the starter relay is disengaged that wire is dead.

There is a wire from the ignition switch to the coil +. I forget what color. Maybe red. It supplies voltage to the coil but first it goes through a resistance wire to step down the voltage to the coil. (to about 7 volts) That resistance wire is frequently pink and is buried in an engine wiring harness. At the end of the resistance wire there is a junction of the brown wire from the starter relay. And a regular wire that goes to the coil + terminal. I think that is brown too.

There is only one wire from ign switch to starter relay. (Red/Blue)
There are two wires to coil.
1) One from ignition switch that supplies lower voltage via a resistance wire
2) The second from the starter relay to coil to supply 12V during cranking only. Getting full voltage to coil on a cold engine helps it to start

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Discussion Starter · #26 ·
@Action at any point were you an instructor? The way explained the ignition system and wiring above made everything extremely clear. I have been reading articles, watching videos and was able to glean a basic understanding of how the pieces work together; however, you filled the gaps. I can’t thank you enough for taking the time to help me out here. If you ever make it to Calgary, Canada my wife and I would treat your to some Western Canadian hospitality!
 

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Thanks for the Kudos

Never been an instructor. My current occupation is not even in the automotive field.
However early in my life right after school I worked for Ford Parts and Service Division. (No longer exists) Out of Seattle. My job was to be out calling on Dealerships in the North West. (US)
I have been to and have a lot of reference material from those days.
Big Corporate politics became my reason to exit the Blue Oval.

I have traveled a lot. Been to 5 of the 7 continents. Never been to Calgary. Closest I got was Northern Idaho. Ironically with Ford Motor Company.

If I could ..... I am just a volunteer on this forum. And if I had my wish it would grow. To that end keep posting and keep posting pictures of your ride.

Again thanks

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