Electrical gremlins NEED help.

[Carolina_Mountain_Mustangs]

Ok David,

think of your cranking circuit like this:

power is supplied to the ignition by a fuseable link located at the battery side of the starter relay.

When the ignition key is turned to the Crank position, power is sent to the park/neutral switch.

if the shifter is in park or neutral (or jumpered) , power is then sent to the S terminal at the starter relay (starter relay has to have a good ground)

There is a coil in the starter relay that when energized pulls a set of contacts together and supplies

power to the starter.

That's how it works.

What you stated in one of your last posts (no power to either of the red wires) at the park/ neutral switch, was the ignition key in the Crank position? if the key was just in the Run position you will not have power to either of the red terminals at the park/neutral switch.

What we want to do here is supply power to the s terminal of the starter relay when the key is in the Crank position.

What you tell us is suggesting that no power is being sent from the ignition switch to the park/neutral switch when the ignition switch is in the Crank position.

SUGGESTING THAT THE IGNITION SWITCH IS BAD OR OT OF ADJUSTMENT

 Not saying that the starter relay terminals S and I cannot be reversed, cause it is possible,

but you still need voltage thru the park/ neutral switch in the CRANK position.

                            Boilermaster

I poured gas in carb and the engine fires if I turn the switch on and short between battery hook up and the starter relay the engine fires up. No fuel in tank. I am thinking now all I need to do is adjust the new ignition switch position. If it works I will be amazed. I had it all together correct except the plug on the turn signal harness which I put together as a mirror image. Headed back to adjust the switch. This car has only been driven 20 miles in the last 25 years. I wanted to take the gas tank off and have it cleaned on Monday. I will celebrate tonight and kill my last two brain cells, lol.

 

[jowens1126]

A buddy of mine could not get his to crank for nothing, but would start when jumping the solenoid. We tried everything under the sun, and nothing worked. Then I told him to reverse the I and S wires and it fired right up with no issues. Im not saying this is your issue, but it is one I have come across.

 

[Carolina_Mountain_Mustangs]

So I am happy. I adjusted the ignition switch and it cranks with the key. Won't crank unless in park so you can use the FMX neutral switch and not have to use the C-4 which is not on my transmission.

So everything works now and what was the biggest culprit was I did not read my own note on the pin layout for the turn signal wire harness.

When you get a new harness, NOS Ford or aftermarket it does not come with the plug end. It is arch shaped and 73 is different that 71 & 72 I am told. So you pop the little red bar out of the center and the small diameter pin sockets come out. You put the new ones on and put the red insert back and you are good to go. Unless you do what I did and I did a mirror image of the correct placement. That is the only plug in the system I could think of that I could have got wrong all others are hard molded. So that was where I went today to try to find something. It helps to have another car to compare to also.

So guys if ever anyone comes up and says when they hook the battery up the right turn signal starts and you cannot turn it off and blows #6 fuse the turn signal wire harness is reversed. Probably never happen again. It was over a year ago that I put the harness on.

This is a picture of the turn signal harness plug I put wire in mirrored.

Thanks for the help of making me thing guys and giving me tips on where to look. I hate electrical stuff. So every wire was pulled from this car from headlights to taillights and every connection and ground cleaned. I replaced the under dash and under hood harness with one that had not bee cut up. So if I can do it anyone on the forum can. I have hard time telling which is positive and negative.

 

[jowens1126]

Great job figuring that out. I find that if you have a suspicion of work you did at some point, thats usually the best place to start. Most of the time my suspicions have been 100% correct when it comes to diagnosing problems I have come across. Especially when its something I did at some point.

I dont like electrical either, but I just re-wired most of the dash harness on my 94 Bronco. It was a bear as there were about 10 miles of wire. But it all worked on the first try. It must have 50 connectors with 4 to 30 wires per connector. I had every one of them apart cleaning, testing, replacing wire, replacing connectors, pins. Something went really bad and burned up about 15 wires, melted them to the core. Im just glad it didnt catch on fire.

 

[boilermaster]

Yee Ha.!

               Boilermaster

 

[midlife]

Oh David...you once contacted me to go through the wiring for this car, but decided to go ahead and work through it yourself. Take 2 aspirins, two good-sized glasses of your favorite adult beverage and go back at it tomorrow. Wiring is not rocket-science, but you do have to think about how best to trouble-shoot things so you can isolate where the problem is. I could probably solve all your problems in an hour or so, but I don't travel well and certainly don't like working upside down with seats in the middle of my back with no AC and 90*+ temperatures. I feel for you...

Should you decide to rip everything out and send it to me, my work is guaranteed so if things don't work after installation, you will know it isn't the wiring I worked on, which greatly reduces what can be wrong.

 

[Carolina_Mountain_Mustangs]

Great job figuring that out.  I find that if you have a suspicion of work you did at some point, thats usually the best place to start.  Most of the time my suspicions have been 100% correct when it comes to diagnosing problems I have come across.  Especially when its something I did at some point.

I dont like electrical either, but I just re-wired most of the dash harness on my 94 Bronco.  It was a bear as there were about 10 miles of wire.  But it all worked on the first try.  It must have 50 connectors with 4 to 30 wires per connector.  I had every one of them apart cleaning, testing, replacing wire, replacing connectors, pins.  Something went really bad and burned up about 15 wires, melted them to the core.  Im just glad it didnt catch on fire.

Good to hear someone else has some adventure left.

 

[jowens1126]

Good to hear someone else has some adventure left.

My wife had a look on here face when I dropped this snake in the living room floor and started tearing it apart.



But I got it all back together after working on it for about 10 days lol.

 

[Carolina_Mountain_Mustangs]

Oh David...you once contacted me to go through the wiring for this car, but decided to go ahead and work through it yourself.  Take 2 aspirins, two good-sized glasses of your favorite adult beverage and go back at it tomorrow.  Wiring is not rocket-science, but you do have to think about how best to trouble-shoot things so you can isolate where the problem is.  I could probably solve all your problems in an hour or so, but I don't travel well and certainly don't like working upside down with seats in the middle of my back with no AC and 90*+ temperatures.  I feel for you...

Should you decide to rip everything out and send it to me, my work is guaranteed so if things don't work after installation, you will know it isn't the wiring I worked on, which greatly reduces what can be wrong.

LOL, the only thing is that I would not have sent you the turn signal harness since it was brand new NOS Ford. I put the plug on as a mirror image. I even read my own notes of which way to view the plug incorrect. Did not have any issues with the under dash or engine harness once I got the pins in the right holes in the turn signal connector.

I still have a couple harness that I bought to get pieces but did not use. I found the one that was complete and not cut anywhere is what went into the car. I am thinking of putting PW in the 72 CJ vert when I do it and will have to alter the harness for that change.

If I had to rebuild one you would see it come your way.

So now on to the air conditioner, lol. Another first time adventure for me. When I got my Mach 1 new came home and took the belt off the air first thing. I only ordered it so it would be there in future, lol.

Thanks for all the suggestions and help you furnish to all us members that are short on wiring.

 

[BeerDontCount]

So I am happy. I adjusted the ignition switch and it cranks with the key. Won't crank unless in park so you can use the FMX neutral switch and not have to use the C-4 which is not on my transmission.

So everything works now and what was the biggest culprit was I did not read my own note on the pin layout for the turn signal wire harness.

When you get a new harness, NOS Ford or aftermarket it does not come with the plug end. It is arch shaped and 73 is different that 71 & 72 I am told. So you pop the little red bar out of the center and the small diameter pin sockets come out. You put the new ones on and put the red insert back and you are good to go. Unless you do what I did and I did a mirror image of the correct placement. That is the only plug in the system I could think of that I could have got wrong all others are hard molded. So that was where I went today to try to find something. It helps to have another car to compare to also.

So guys if ever anyone comes up and says when they hook the battery up the right turn signal starts and you cannot turn it off and blows #6 fuse the turn signal wire harness is reversed. Probably never happen again. It was over a year ago that I put the harness on.

This is a picture of the turn signal harness plug I put wire in mirrored.

Thanks for the help of making me thing guys and giving me tips on where to look. I hate electrical stuff. So every wire was pulled from this car from headlights to taillights and every connection and ground cleaned. I replaced the under dash and under hood harness with one that had not bee cut up. So if I can do it anyone on the forum can. I have hard time telling which is positive and negative.

Well that settles it then.  I needed a reason to get another Mustang in the corral and now I have it, just in case I need to diagnose something.  I'm sure the wife will buy that argument.  Thanks David!