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Discussion Starter #1
I am installing a 4R70W into my 1989 T5 fox and would like a little clarification.
The 4R is from my 2001 mustang giving it the digital sensor and based upon the USSHIFT manual I am to wire in teh neutral safety switch into the main harness. No biggie, but when I scan the instructions pages 16/17
http://www.usshift.com/downloads/4R70Wmanual.pdf
I notice that the wires offered for the neutral safety switch have a diagram for either wiring into the starter circuit or the clutch switch.

any advice on this?
Sorry if I am not clear on my problem as I am dead tired and hungry.
Basically, where do I connect the 2 wires from my transmission controller and what do I do with the clutch switch and the T5 neutral safety switch.

Thanks,
Mike
 

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neutral safety switch came in auto foxes

clutch safety came in manual foxes

if you jump either, the safety is removed

if you look at how foxes are wired you will see what they do.

like in the other thread, they came with different trans harness for speed of assembly

you get the correct harness,,,,,,or you have a rewire nightmare,,,,,,cause if you do it wrong, you will short traces in the ECM.
 

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Discussion Starter #4
correct.
It seems that the trace that will get burned is the one on the EEC pin #30. Auto and manual computers are different in regards to pin #30 to prevent the voltage spike.

I am using the USSHIFT module and it is supposed to be designed for the manual to 4R swap. I have tried to read nearly all of the T5 to 4R swaps and I haven't seen any of them state that replacing the harness is necessary. Don't get me wrong, if it is necessary I will, but it doesn't seem like it is necessary from the numerous threads and the USSHIFT manual.

Putting a jumper in the starter relay circuit at the clutch interrupt switch would be very similar to the Auto wire harness.

Leaving the cruise interrupt connector unplugged seems to be the way the factory did it as this connector is used to complete a circuit that sends voltage from the brake lights to the cruise control module to inactivate it.

With all that said it seems to make teh most sense to wire the USSHIFT module into the starter interrupt wires that I am jumpering above as the 4R range sensor will be the new clutch interrupt switch.

Now I just need to figure out what to do with the Neutral Gear Selection connector that went to the manual trans and pin #30.
 

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you don't have to replace harnesses, its just much easier to do so, and doesn't look like some shrink tubing hack job, inviting corrosion.

go to bbb industries and get the wiring diagrams.
 

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Discussion Starter #7
alright
after some head scratching and a phone call this is how I am setting things up.

Clutch switch and clutch pedal will be removed

Clutch switch cruise interrupt connector will just get taped up as if it was never there as the brake switch will take care of interrupting cruise.

Clutch switch starter interrupt circuit will be disconnected, but instead of jumpering the wires I will connect them to the leads of the transmission neutral gear selector. Basically, when teh vehicle is in park or neutral it will complete the circuit just like the clutch switch did.

I will leave the automatic neutral drive switch wires looped as they are from the factory. I still think that I can wire in the automatics neutral safety switch here as this is the same circuit as the clutch starter interrupt switch based on numerous wiring diagrams. All roads leads to the P/Y wire going to pin#30 whether it is a manual or automatic. Burning the trace is only an issue in regards to O2 sensor harnesses.

The T5 neutral gear selector seems to mainly be used for key-on code dumping and testing, so I will most likely wire this to a switch or at least keep the wires accessible. It will stay in a closed circuit unless I need to clear/access computer codes and at that point I would open the circuit.

I will wire in the factory O/D switch on my 2001 shifter to the Quick1 controller

I will use the Quick1 controller vehicle speed output to drive my electric fan shutoff.

Let me know if this gives anybody heart burn.
 
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