Speedometer VSS hook up after SYE install

[RAH66]

Here's where I'm at: Transfer case has a 3 wire speed sensor (VSS), and my Jeep is a 2 wire VSS stock.

 

The parts I have:

Dakota Digital Universal Speedometer Signal Interface SGI-5E (USSI)

Add-a-circuit

3 wire pigtail connector

plenty of wire

 

 

 

I think with my tire and gearing combo I'm about as close to stock ratio as I could be, but I figured I'd get the signal converter to have complete control make my life easier if anything ever changes in the future.

 

I have 2 questions:

 

Question 1

To power the USSI, I got an add-a-circtuit to get 12v from the footwell fusebox.

 

What would be the best socket to draw power from?

 

I'm thinking I'll use the unused POWER CLOCK 10 amp socket for power. However, since the GAUGES are 7.5 amp, should I stick with 7.5 amps and stick my add-a-circuit in there? Or just use a 7.5 amp fuse in the 10 amp POWER CLOCK socket? Or some other fuse / socket entirely? I can't seem to find any info on how many amps the USSI needs.

 

 

 

Question 2

I tried tracing the stock speedometer wires to the gauge cluster, but once it meets up in the harness in the engine bay I have no idea where it goes. 

 

Does anyone know where the two stock speedometer wires are that I can send the modified USSI signal to?

 

If that's unfeasible, I suppose I could just send the modified signal wires back to where the stock wires used to connect to the VSS. Seems a little messy, but if the alternative is risking damage to my gauge cluster or something else in the cramped area under the dash, I can live with it.

 

 

I appreciate any guidance!

[gogmorgo]

What tcase are you using? Can you not just reuse your 2-wire sensor?

 

The wires for the trans run up the firewall to the passenger side of the head, where they connect to the main engine bay harness, IIRC.

 

[RAH66]

I installed a Slip Yoke Eliminator which uses a hall effect speed sensor instead of the gear driven speed sensor that came stock.

[DirtyComanche]

29 minutes ago, RAH66 said:

I installed a Slip Yoke Eliminator which uses a hall effect speed sensor instead of the gear driven speed sensor that came stock.

 

You're not going to want to hear this, but I'd sell that SYE and install the normal short HD one from AA, and use your normal 2 wire VSS.

 

That Dakota Digital converter box is a hack piece of equipment at the best of times.  I'd go out of my way to not have it.

[RAH66]

Well... that's unfortunate.

 

Theoretically, according to this post, I don't need the signal converter, as long as I supply 5v to the new VSS. I can try that if this thing doesn't work out.

[DirtyComanche]

3 hours ago, RAH66 said:

Theoretically, according to this post, I don't need the signal converter, as long as I supply 5v to the new VSS. I can try that if this thing doesn't work out.

 

I'd read that before, and I believe it is accurate, but have never tried it.

 

This is going into a Comanche?  The super short SYE carries a price premium with no gain in our application, curious why you wound up with one?

[RAH66]

4 hours ago, DirtyComanche said:

 

I'd read that before, and I believe it is accurate, but have never tried it.

 

This is going into a Comanche?  The super short SYE carries a price premium with no gain in our application, curious why you wound up with one?

 

Honestly just a misunderstanding on my part of the SYEs and Speed Sensors. At the time I ordered it I still wasn't sure what size gear and tires I was gonna go with, so I got the one with the electronic speed sensor thinking that was the only one I'd be able to easily reprogram after the fact. I realize now that I didn't need it, but oh well.

[RAH66]

Alright, got it working! Here's what I ended up doing, for anyone else curious.

 

 

 

 

Anyone else with more electrical experience than I see any red flags with this setup?