Electrical Box of Spaghetti

kraze1

Member
Feb 16, 2010
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Philadelphia, PA
Hello everyone. I bought a clean '89 LX 4cyl roller to do a 5.0 swap. The previous owner did a 5-lug conversion w/Cobra brakes and planned on doing a 5.0 swap, but gave up on her & gave me a bunch of v8 parts in plastic bins. I was able to install the fuel & brake lines. All of the wiring for the car was in one of the large bins...unlabeled. For the most part, through research and internet pics, I figured out the wiring under the hood. The dash wiring has me stuck! I looked at veryuseful.com's diagrams and they are helpful, but what would really be a lifesaver would be a complete wiring schematic with an exploded view that really shows where everything goes. Right now I have a huge wad of wires and brackets coming out from under the steering column & I have no idea what the proper routing of the harness is.

Additionally, while doing my research I was able to look up the white box under my dash and found that it is a "Speed Control Amplifier" and is tied into the cruise control system. I'm installing a 5-speed manual T5, so it will not have cruise control. Do I need to keep this box plugged in & run the wiring outside the car, or can I eliminate it altogether? If I do not connect the speed control amp or the connections behind the fender, will it affect anything else?

Thanks in advance for your help!

- E
 
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jrichker

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@kraze1

PM me your email address and I will send you a complete Ford Factory 89 Mustang electrical diagram set. The zip file is 2.5 MB and is too big to fit through Stangnet's email gateway.

The plug shapes on the diagrams match the plug shapes on the actual plug. The diagram is divided up by the layout of the car. The first diagram is for the very front of the car, and it works its way to the rear of the car page by page.

They are in a zip file format to reduce the size of the package. If you don't have Windows 7 or Windows 8, or later, you’ll need WinZip or other Windows archive tool to extract them from the zip file.. See www.majorgeeks.com - Download Freeware and Shareware Computer Utilities for a free download.

You will need the Adobe Acrobat viewer which is also a free download – www.adobe.com/products/acrobat/readstep2.html - Adobe Reader download - All versions
 
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kraze1

Member
Feb 16, 2010
6
1
13
Philadelphia, PA
@kraze1

PM me your email address and I will send you a complete Ford Factory 89 Mustang electrical diagram set. The zip file is 2.5 MB and is too big to fit through Stangnet's email gateway.

The plug shapes on the diagrams match the plug shapes on the actual plug. The diagram is divided up by the layout of the car. The first diagram is for the very front of the car, and it works its way to the rear of the car page by page.

They are in a zip file format to reduce the size of the package. If you don't have Windows 7 or Windows 8, or later, you’ll need WinZip or other Windows archive tool to extract them from the zip file.. See www.majorgeeks.com - Download Freeware and Shareware Computer Utilities for a free download.

You will need the Adobe Acrobat viewer which is also a free download – www.adobe.com/products/acrobat/readstep2.html - Adobe Reader download - All versions

@jrichker Thank you. This will certainly help a lot. I will send you my info right away.
 

Blown88GT

Founding Member
Nov 13, 1999
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...

Additionally, while doing my research I was able to look up the white box under my dash and found that it is a "Speed Control Amplifier" and is tied into the cruise control system. I'm installing a 5-speed manual T5, so it will not have cruise control. Do I need to keep this box plugged in & run the wiring outside the car, or can I eliminate it altogether? If I do not connect the speed control amp or the connections behind the fender, will it affect anything else?
....
You don't need to plug it in & you can eliminate almost all the wiring to it.
However, the factory ECU & the Speed Control use the VSS (Vehicle Speed Sensor) which is attached to the T5.
VSS needs to be connected to pin-3 & pin-6 on the ECU.