[b3lha]

Originally Posted by oab_au

The Aussie has an inductive pick up for both sensors, in side the box.

It appears that the JDM has a Hall Effect sensor for the No.2, and an inductive pick up for No.1.
This is probably due to not being able to fit an inductive pick up in the front diff. The inductive has to rotate a magnet, with a winding beside it. The Hall Effect spins a shutter wheel, with the chip in the center of it.

The output is different, the inductive is a AC signal, of at least 1V p/p, the Hall is an 5V square wave. The outputs may be compatible, if the TCU uses a Smitt Trigger input, it would still register the pulses, regardless of one being zero crossing, and zero to 5V.

The other differences are,
A. that the Hall needs a 5V feed to it, that the Aussie does not.
B. that the output of the JDM/US is at road speed, so it can be a true speedo feed. The Aussie has the final drive ratios between it and the road, so it has to be divided by the final drive ratio before feeding the speedo.

Great. Now we know.

As you suggest The White output wire could be feed to the speedo, but it also needs to go to the TCU so it can see the difference in front/rear speed sensor outputs, to operate the Limited slip clutch. Whether the TCU can just handle the two different signals, the No.2 at road speed and the No.1 at tail shaft speed, as base, and then look at variation to work the LSC, I don't know.

I'm not suggesting connecting a white wire (inductive) feed to the speedo. Sorry if I'm not explaining this very well.

If you look at the diagrams, there is no white feed to pin a17 of the TCU on JDM cars. I checked this on my own cars. The Yellow/Red feed goes straight to pin a11. I think that pin a11 is the signal that the TCU looks at to measure the wheel speeds and control the clutch.

I'm convinced that the TCU does not use the inductive signal at all. It goes into pin a17, gets converted to a hall-type signal then comes out on pin c6. Then that hall-type signal goes back into the TCU on pin a11 just like on a JDM car.

The wiring changes look pretty straightforward to me. Just use the existing white wire to carry the signal from the diff sensor to the TCU. Connect Power, Ground and White to the diff sensor. Then snip two wires are the TCU and solder them together.

I suppose it would be a start to do this and see the effects, the other way would be to fit the Aussie No.2 inductive pick up to the JDM box, and leave every thing the same.

I think that Joe did something similar to this. He used the innards from a new UK gearbox to repair his broken JDM one. I guess the choice comes down to whether you are more comfortable splicing wires or building transmissions.

Phil.