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Eec Main Harness Questions

  • Thread starter Thread starter 86lxhatch
  • Start date Start date Sep 7, 2012

86lxhatch

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Nov 14, 2011
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Sep 7, 2012
#1
  • Sep 7, 2012
  • #1
I went carbed, but was wondering if I have to have the computer powered to run the factory tach, or if it will run off of the cluster which has power from the other harness.








Also, I am removing all of the wires from the computer harness main plug that I don't need anymore(removing them with a pin-out tool from the harness plug)

If I need to have the computer on for the tach to function, is there a simple diagram that shows the colors on the plug and where they go? I copied a wiring diagram from this site the other day, but it doesn't show where the wires go on my computer, the wires just run off the end of the page...I guess I'm not savvy enough to put the "big wiring picture" together!! The plug is numbered to correspond to the colors...

So I guess at the minimum I will need the relay, power wire, ground wire, switched 12v ignition power wire, and tach wire, right?
 

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jrichker

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Sep 7, 2012
#2
  • Sep 7, 2012
  • #2
The tach draws DC power from the circuit board it is mounted in. The signal to drive the tach is the IDM pulse off the TFI module.

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif
 
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