Electrical AOD to T5 VSS

sav22rem22

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Feb 6, 2020
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Hello all. This post is more just to get a reminder of what needs to be done regarding the VSS sensor when swapping to a T5 from an AOD. I can't remember if I've mentioned it in the past or not but I've ultimately come to the conclusion that my car was swapped from an AOD to a T5. I'm wondering what I need to do to make sure my ECM sees my VSS sensor signal. Do I need a manual trans harness? I remember seeing something about having to run your own wires to the ECM from the VSS however that could've been for a speed density to mass air conversion. Thanks for any info. My car is an 89 GT
 
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Mustang5L5

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Mod Dude
Feb 18, 2001
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89 GT would already have the vSS wired to the ECU. It’s the 86-88 cars that have this wiring issue as the VSS was only used for cruise control those years.

all you need to do is take VsS out of AOD and put it in the T5
 
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Willybill32

But at least it's tight!
Jul 16, 2019
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OK...a question. I have a non-cruise control '86 that I converted to mass air years ago. The instructions for my Ford MAF kit addressed the VSS wiring, but since I didn't have the VSS, I didn't have anything to connect. Is this an issue? I've never had a problem to my knowledge.
 

Mustang5L5

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Mod Dude
Feb 18, 2001
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My 88 was the same being it was non-cruise.

the harness is clipped to the crossmember, so I added the VSS and speedo csble made for a VsS sensor.

the wiring is present, but only used for cruise control. I tapped into the two wires in the drivers kick panel, and added them to the ECU harness. The mass air kit I bought had three spare wires with ECU pins crimped in. Two for VSS and one for fuel pump monitor
 
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Willybill32

But at least it's tight!
Jul 16, 2019
279
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Lexington, KY
My 88 was the same being it was non-cruise.

the harness is clipped to the crossmember, so I added the VSS and speedo csble made for a VsS sensor.

the wiring is present, but only used for cruise control. I tapped into the two wires in the drivers kick panel, and added them to the ECU harness. The mass air kit I bought had three spare wires with ECU pins crimped in. Two for VSS and one for fuel pump monitor
Am I missing anything with not having done this? Also, I've been under my Mustang a lot, and don't remember seeing any wiring on the crossmember. Do you have pictures? Don't go out of your way, but if you're down there...

Thanks!
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,433
12,338
224
Massachusetts
Am I missing anything with not having done this? Also, I've been under my Mustang a lot, and don't remember seeing any wiring on the crossmember. Do you have pictures? Don't go out of your way, but if you're down there...

Thanks!

unfortunately I can’t take pics of the prior state because the VSS is now plugged in and functional.

Maybe 1986 is different, but in my non-cruise ‘88 had the VSS wiring capped off and clipped here on the X-member
6F709077-9E75-46CF-80FF-8A8660E9B15C.jpeg

easy way to tell is look at the bundle of wires that comes into the trans tunnel. On a msnual car there are three connectors. One for the reverse lights, one for the NGS on top of the T5 and one for the VSS. AOD cars won’t have the NGS plug so they should have two.

if for some reason Ford didn’t equip non cruise 86 cars with the plug, you can either change the harness, or just run two pins back to the ECU. I believe pin 3 and 6. Polarity doesn’t matter
 
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Willybill32

But at least it's tight!
Jul 16, 2019
279
109
53
Lexington, KY
unfortunately I can’t take pics of the prior state because the VSS is now plugged in and functional.

Maybe 1986 is different, but in my non-cruise ‘88 had the VSS wiring capped off and clipped here on the X-member
6F709077-9E75-46CF-80FF-8A8660E9B15C.jpeg

easy way to tell is look at the bundle of wires that comes into the trans tunnel. On a msnual car there are three connectors. One for the reverse lights, one for the NGS on top of the T5 and one for the VSS. AOD cars won’t have the NGS plug so they should have two.

if for some reason Ford didn’t equip non cruise 86 cars with the plug, you can either change the harness, or just run two pins back to the ECU. I believe pin 3 and 6. Polarity doesn’t matter
Thanks for the response! I’ve had the crossmember out a couple of times recently and there was no wiring there. Next time it’s up in the air I’ll look again.