Need help with some wiring

[wolverine8490]

I am working on changing over a 96 V6 auto mustang, to a 5.0L manual from a 91. Basically, I was wondering if someone could check voltage at a wire for me. I need to know how much voltage is at the Gray/red wire at the data link connector.

From what I see in the wiring diagrams, the wire should have 12 VDC when the ignition is in the start position (turned all the way, like you were starting the car). Here is a pic of what the DLC looks like. Can someone help me out. This is the last wire I have to hook up. I just dont want to fry anything.

[quik lx]

Do you have a voltmeter? If not radio shack has cheap ones!

[wolverine8490]

Yeah, I have one. But I dont know what it was originally supposed to have. I have all the wiring diagrams and am trying to wire it all up.

The BAP, TPS, ACT, and ECT all run through the clutch nuetral switch system. The car has 3 clutch safteys. A Neutral Saftey Switch, a Neutral Start Switch, and a Neutral Sensing switch. The wiring for the switches run through all the engine sensors, and back to the ECM. On an Automatic car, the ECM wire that runs to all the switches on the manual cars just goes straight to the ignition switch.

This is very difficult to explain in writing. Basically, I just need to know if I can bypass all of the neutral saftey garbage, and run the wires straight from the ECM, to the sensors. Or when the car is running, and you push in the clutch, does that change settings to the sensors.

Here is a diagram of what I am wondering

[dedpedal]

I have a factory Ford wiring manual for a 90 or 91 mustang. Youre welcome to borrow it if you need it.

[wolverine8490]

I have a factory Ford wiring manual for a 90 or 91 mustang. Youre welcome to borrow it if you need it.

I may take you up on that if I can't figure this out. I have a bunch of diagrams, it is just understanding them that is the annoying part. I think I may have figured it out. It looks like like I am getting around 4.70vdc to the gry-red wire on the STO connector. I guess it is pulling its power from the ECM. It is still wierd taht on the auto, it goes straight to the Ignition switch. I guess the manual and the auto ECC's are different.

[Sparky]

I may take you up on that if I can't figure this out. I have a bunch of diagrams, it is just understanding them that is the annoying part. I think I may have figured it out. It looks like like I am getting around 4.70vdc to the gry-red wire on the STO connector. I guess it is pulling its power from the ECM. It is still wierd taht on the auto, it goes straight to the Ignition switch. I guess the manual and the auto ECC's are different.




They are different. You need to wire the harness according to which ecm you have. Autos have 12V's running through the neutral switch and manuals are merely a signal return. If you wire them wrong you will fry the ECM The difference is in the HEGO harness (oxygen sensor harness). It's kind of dumb that the circuit runs through this harness but there are harnesses for an auto and for a manual. I had an auto harness for a manual and found out the hard way. I repinned mine however and fixed the problem. It was only one wire that needed changed if I remember.

[Sparky]

And to answer your origional question, wire them the way ford wired them. The neutral gear switch is used to tell the car when you are stopped or slowing down so it can change to a different set of parameters to keep your car from dying at the stoplight. It might not affect you so much if you're stock, but my GT40 engine had a bad hanging idle problem without it being hooked up. You can bypass the switch so your starter will engage, but I don't recommend deleting it from your signal return circuit.

[wolverine8490]

And to answer your origional question, wire them the way ford wired them. The neutral gear switch is used to tell the car when you are stopped or slowing down so it can change to a different set of parameters to keep your car from dying at the stoplight. It might not affect you so much if you're stock, but my GT40 engine had a bad hanging idle problem without it being hooked up. You can bypass the switch so your starter will engage, but I don't recommend deleting it from your signal return circuit.

Yeah, see that what I was thinking too. I figured there had to be a reason that it would only send voltage to those sensors with the clutch pushed in. I have read so many different things about it. I did sit down and figured out how the switches all ran. What a pita that was. The only thing I dont understand is that how would the ECC know what to do if it were an automatic. But I guess that is what makes the ECC's different.

[wolverine8490]

They are different. You need to wire the harness according to which ecm you have. Autos have 12V's running through the neutral switch and manuals are merely a signal return. If you wire them wrong you will fry the ECM The difference is in the HEGO harness (oxygen sensor harness). It's kind of dumb that the circuit runs through this harness but there are harnesses for an auto and for a manual. I had an auto harness for a manual and found out the hard way. I repinned mine however and fixed the problem. It was only one wire that needed changed if I remember.

So I guess the wiring diagram was right. I hope I didnt fry my ECC. I was pissed and drunk the other night and said the #^$$ with it, and hooked it up to the ignition switch. The next day I realized that I really needed to do it right, so that is what I did. The ECC is still sending 4.7VDC to the sensors which from what I have read is correct. I then sat down and wired all the saftey systems up outside of the car, and finally figured it out. I figure what I will do is try it without all the switches first, and if it causes problems, then do it the right way. It really should only take a few hours to wire it the way ford had it originally.