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Hi, I'm in search of some information, hoping I can be pointed in the correct direction.. 

 

Car is a s15 coverted to awd using a donar r33 gts4 for parts..  We have removed the abs from the orignal s15 from factory..  How can I get my haltech to read the speed sensor signal from the transmission? The transmission is stock but planning to upgrade to a os88 box soon.. What can I use to solve this issue? 

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https://www.sau.com.au/forums/topic/484227-s15-rb26-awd-conversion/
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The Nissan speed sensor just sends an AC (actually it's more of a saw-tooth waveform, but it fluctuates +ve and -ve) signal to the (factory) dash. That signal's frequency is proportional to the speed. The speedo head then converts that to a square wave 0-5V PWM signal that is put out on the "speed signal" bus wire that is connected to the ECU and any other CU that wants to know vehicle speed (which in an S15, is....probably not very many. Did they have HICAS?). That signal can be fed directly to the Haltch, the same as it is fed to the factory ECU.

All this is in the factory service manuals.

You just need to read the Haltech manual on what you need to do to configure an input to read a PWM signal like that and connect the wire.

But that's assuming that you are using the S15 dash. If instead you are going to use a Haltech dash then you could probably also read the Haltech manual to find out what you have to do to instead connect the AC signal direct from the speed sensor.

This setup will work and be an improvement over the factory speed sensor (quicker to respond and more accurate). 

https://shop.ostdyno.com/shop/shop/nissan-skyline/engine-management/r32-gtr-auxiliary-speed-sensor-kit/

If you want a simple plug and play option, this will work too. 

https://www.haltech.com/product/ht-011310-gps-speed-input-module/

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