I've looked over a few schematics and diagrams, but I'm still a little confused.

I just replaced both wiring harnesses in my 66's engine compartment. Everything is clean and new, and it starts up without a problem (jumping the solenoid). The person that owned it before me apparently didn't know why it wouldn't key start (carbureator was clogged, fuel lines were clogged, etc.) so they tried to get the ignition switch out, couldn't, broke it, and cut the wires.

To make a long story short, I have a new ignition switch ready to go in, but I want to make sure the underdash harness is still good (I'm praying...). I used to be able to start it with the wires from the ignition switch, but something must have burnt out at some point; they no longer work.

First of all, which wires should I be jumping just to crank it over? I never really paid attention... just touched a couple until I got something.Second, is there a fuse that could have blown somewhere, or is the underdash harnessprobably screwed? Anything else that I can check?

Thanks.

 

Sounds like you need to check a wiring diagram first.

With it and enough time and patience you will be able to find if there is a problem and also how to wire in your new ignition switch.

 

+1
IMO- it seems like a good thing them wires shorted out so you now have motivation to fix it properly and have piece of mind.

Good luck!
-Hawkins

 

True, but it also only appears to be the ignition switch wires that are cut. I'd definately prefer to avoid the $400+ for the underdash wiring harness, and the trouble of installing it.

Is there a fuse box on these cars, or no? If there isn't, I could be in for some fun times...

 

I had to figure the posts on the ignition switch out myself using a test light. After much consternation I had to accept that the big center terminal was the accessory terminal... after I finally accepted thisreality I figured out the rest of the switch.... I can't remember which was which now except that the center is accessory...

 

lo ...

all without warranty ... ;-)

equip yourself with voltmeter. or working test light.
there should be a yellow cable going to where the ign switch was. This should hook up to port B (battery) on ignition switch.
This yellow cable is constant +. no matter what they key does it always will be +. If it's not + check fuses.

I don't know where the fusebox in 66 is, but it definetly has one and in my case (64) it's above the drivers kick panel (inner fender under dash).

If you have plus on yellow you're good to go.

There should be a Red-Blue cable, which goes to neutral-safety switch (if you have an automatic) and from there to starter relay.
This red-blue cable should hook to the S (starter) port of ignition switch.

As well you will need the Black-Green cable for ignition. It goes to the A port of ignition switch (alternator?).

So once you power the black-green one with 12V (ie hook it up to the yellow cable), your ignition should come on. (oil pressure warning light, alternator warning light should come on).

If you have this, keep them connected to try and start. so basically twist them so they stay together temporarly.

Now the starting:
Make sure you're not in gear (manual), or that you are in parking on the automatic.
as long as you connect the Red-Blue cable to the other 2 that you already hooked up the starter should be turning.
Once the engine starts, disconnect the 3rd (red blue) from the other 2. that should release the starter. (so basically only hold the red blue against the other only touch it to the other 2 for starting).

If ignition works (lights come on), but starter doesn't move (you said the starter is ok when you bridge the relay):
the neutral safety switch might be faulty.

Disconnect the 2 cables at the neutral safety switch. and connect them permanently to each other (twist them). Make sure they don't hit ground (tape em up).

If it then works perfectly fine: get a new neutral safety switch.

any other problems let us know (please give details on what works and what doesn't)

Kalli

 

Kalli,,
I believe you just taught us all how to hot wire his car!! Thats great!!!

[8D]

 

yep. thats about the size of it.
every car thief knows at least those basics or how to torture a screwdriver with a hammer ... ;-)

forgot another info ... don't leave the car for too long in ignition status. I've heard more than once that people fried their ignition system by leaving it on for a period of time (listening to radio etc).

Kalli

 

Heres a few good sites i came across that should help you alot;

Wiring diagrams for classic Mustangs:
http://www.hammar.dyndns.org/~djhamma/wiring.htm
More wiring diagrams:
http://pic10.picturetrail.com/VOL326.../168993896.jpg
EVEN More Wiring digrams: 1964-72
http://www.themustangshop.com/index..../resources.cfm

How to replace 65-73 Mustang Ignition Switches.
http://www.mustangmonthly.com/howto/...hes/index.html

Hope this helps!
-Hawkins

 

Nice links Hawkins, people seem to forget that we have most of these in our FAQ setion. FYI- I get a bounced server message when I try to open your second post though.