Name that wire

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1973 mustang sportsroof - 351c 2v - fmx trans.
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That routes around to the starter solenoid @ the battery + side. It's the accessory feed wire for power windows, power top, various accessories that demand more current. It should have a 3 hole female bullet connector under the left kick panel.

 
Dashlights are fed power from the headlight switch (Light blue-Red #19) directly off the headlight switch, then to the fusebox (short, 3 amp fuse) and the Turn Signals are fed thru the accessory feed of the ignition switch (Black-Light Green #297). This also feeds the windshield wipers. Power from #297 goes thru the Acc fuse then becomes wire #296 (White-Purple) to the flasher unit, then it becomes wire #44 (Light Blue) then to the turn signal switch in the steering column.

Do your emergency flashers work? Do you have +12 volts at the black-light green side of the turn signal flasher?

I'd suspect for the dash lights a poor connection at the fuse box or bad headlight switch.

For the turn signals, I'd suspect the flasher unit then the turn signal switch, although I wouldn't rule out the ignition switch.

Look at the top of the main page of the website and you see a "Data" tab. Under it are PDF's of the wiring diagrams of the cars. That's what I've been reverencing for the above wire numbers and colors. If you can read a street map, you probably can read the wiring diagrams. If not, don't worry. Check for the presence of +12 volts at the above points and let us know if the other accessories work OK, then we can troubleshoot from there.

Do you have a volt meter or a test light?? You'll need one or preferably both for this. More tools, Yeah!

 
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Thank you for the in depth and very informative response, I really appreciate your time. I will check out everything you mentioned on wednesday. I cleaned up all of the connections at the fusebox and replaced all of the fuses with new ones and there was no change. The headlight switch I got off of a parts car that sat for many years so really dont know if it is working 100%, the headlights, taillights, tag light and all running lights are working though. The headlights will go bright/dim but no indicator light on the instrument panel. No horn, lighter, turn signals, blower fan, trunk light or dashlights work at this time.

Thanks again for you time.

 
Thank you for the in depth and very informative response, I really appreciate your time. I will check out everything you mentioned on wednesday. I cleaned up all of the connections at the fusebox and replaced all of the fuses with new ones and there was no change. The headlight switch I got off of a parts car that sat for many years so really dont know if it is working 100%, the headlights, taillights, tag light and all running lights are working though. The headlights will go bright/dim but no indicator light on the instrument panel. No horn, lighter, turn signals, blower fan, trunk light or dashlights work at this time.

Thanks again for you time.
Horn is powered directly from the fuse box, tied together with the lighter (lower most left hand fuse). The blower fan is on its own circuit (uppermost right fuse). The horn routes through the turn signal switch, so I'd be suspicious there, but since the lighter doesn't work, I'd place my bet on the fuse box. Trunk light is tied to the courtesy lights, lowermost right fuse.

 
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Just went out and checked all the fuse locations with a digital multimeter, all fuses/ terminals show around 6.80ish volts, except fuse #3 which is reading around 3 volts with key in on position. Battery show 12.85 volts. Right now I only have the battery hooked up with the large yellow wire straight to battery positive, large heavy guage wire from battery negative to chassis gound, small black& white wire to ground also. Currently the car has no engine, trans, starter relay or regulator hooked up. I am just trying to figure out whats what with the cars electrical system before dropping the engine and trans in. Thoughts and thanks again for your time :-}

 
Just went out and checked all the fuse locations with a digital multimeter, all fuses/ terminals show around 6.80ish volts, except fuse #3 which is reading around 3 volts with key in on position. Battery show 12.85 volts. Right now I only have the battery hooked up with the large yellow wire straight to battery positive, large heavy guage wire from battery negative to chassis gound, small black& white wire to ground also. Currently the car has no engine, trans, starter relay or regulator hooked up. I am just trying to figure out whats what with the cars electrical system before dropping the engine and trans in. Thoughts and thanks again for your time :-}
Mike

If you're seeing 6.8 volts, you're seeing the middle of a resistance feed. On the small black&white wire, what size ring terminal is on the end of it? I'm looking at the wiring diagrams and I don't see a black&white wire that would be near the starter relay. There is a black & yellow power feed wire that should be connected to 12 +.

Fuse #3 showing lower voltage is the dash lights thru the dimmer switch, therefore it's a resistor and you should see less than full circuit voltage unless turned full right to where the courtesy lights come on.

Curtis

 
Just went out and checked all the fuse locations with a digital multimeter, all fuses/ terminals show around 6.80ish volts, except fuse #3 which is reading around 3 volts with key in on position. Battery show 12.85 volts. Right now I only have the battery hooked up with the large yellow wire straight to battery positive, large heavy guage wire from battery negative to chassis gound, small black& white wire to ground also. Currently the car has no engine, trans, starter relay or regulator hooked up. I am just trying to figure out whats what with the cars electrical system before dropping the engine and trans in. Thoughts and thanks again for your time :-}
The center taps on the bottom are battery power; the center taps on the top of the fuse box is ACC power. If these are not reading 12 Volts, you're losing voltage somewhere between the battery and the fuse box, and that's not good at all. Check for corrosion at the solenoid switch for your main harness power lead. Another idea is to disconnect the headlight harness from the main harness (that's at the fuse box) and measure the voltage on the headlight harness (largest pin): that's battery power. If not 12V, the problem is in your headlight harness. If that is 12V, then the problem is probably at the ignition switch or the main splice that takes the battery power from the headlight harness connector and distributes it to the headlight switch, ignition switch, and fuse box. I have never seen that OEM splice fail, however.

 
Okay cleaned up the ground wire connection and it is now getting 12 volts to the fuse box, the 2 smaller fuses are not getting any voltage readings at all. The dimmer function on the headlight switch is working on the 1 working interior light I have by the ac controls. Still no horn, turn signals, blower fan or instrument panel lights. I will keep trouble shooting til I figure it out. Couldnt find a black/yellow wire anywhere, where does it come through the firewall at? you guys are the best!


Man the previous owners sure left my head spinning, here is a pic of a couple more unhooked connectors. Guesses?

http://s59.photobucket.com/albums/g292/mmanns69/Snapbucket/?action=view&current=BF62CA3D.jpg

 
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OK...you're not getting power to the fuse box for the dash lights. I believe the interior lights by the A/C controls are from a different circuit entirely. Before you take your system down, find a way to access your headlight switch connector. Find the blue/red wire (it will be at one of the corners) and tug on it and make it straight. Many times, the crimp doesn't make a good connection at the pin inside the headlight connector. Now test to see if you have voltage at the fuse box. Remember, the headlight switch has to be out, and I believe rotated all the way counterclockwise to turn on the dash lights to their maximum.

 
Hehe, thanks for letting me borrow your picture for a reference, you know they say a picture is worth a 1000 words so you saved me alot of typing lol. Anyway thanks for the tips everyone, I picked up a NEW headlight switch and headlights and will check out all recommendations tonight, currenty it is 108* outside and has been that way for the last week, yay!

 
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