Thread: Fitting C6100-4 Radio Interface Unit

Top stuff good write up.

Just in case people don't notice the name Slunnie is actually a link to the other post PeterM is referring to.

www.slunnie.com :: View topic - Truespeed speedo correction installation

Perfect timing. I am about to do this myself tomorrow.

Hi, sorry about this very crap drawing, so what i have done is the right way? I read the online tutorial by sunnie but the last part i dont really understand (sorry) as it doesn't mention any specific colors to the SCU.

Any help will be fanastic

Originally Posted by Kaaaiju

Hi, sorry about this very crap drawing, so what i have done is the right way? I read the online tutorial by sunnie but the last part i dont really understand (sorry) as it doesn't mention any specific colors to the SCU.

....

I can't say for sure, but I'm thinking No!

As I read this tute, he's saying that there are 3 wires on the SCU. Is that right?

If not, didn't it come with a install diagram/instructions?


On your drawing, you have brown wire connected to the cut pink/green wire out of the SLABS.
PeterM says to connect the white wire from the SCU to the cut Pink/Green wire coming from the SLABS.

The other end of the SLABS cut wire(going to the speedo) requires the green wire from the SCU.

This is according to PeterM's tute.

I've told my brother to get one of these for many years now .. stupidly(but not entirely wastedly) he got a speedo corrector from Jaycar.
Stupidly! .. we can confirm that it doesn't work. Not wasted effort, we did confirm that it doesn't work .. so no one else has to waste their $s to confirm this now.

Anyhow, we did connect it up and even tho I said it doesn't work .. not entirely true. It partially worked, just not very well.

But, for the C-6100 you need to connect it's wires thus:

Red = ignition
Black = ground
Brown = nothing!!
White = cut pick/green wire still in the SLABS plug(ie. to SLABS) Hopefully you used connectors on the wire ends.
Blue(or Green) = to other end of cut wire (leading away from SLABS/plug, which goes to speedo)

note on the blue/green anomaly. PeterM says in his tute that there is a green wire, seems you have a blue wire on your C-6100. What I've found that on the C-6100 there have been both colours .. both = ouput signal to the speedo.

What we did on bro's is to hook up onto cut wires a male/female spade connectors. red or blue types both work equally well(for the cable size). This way you can remove SCU at any time, and reconnect spade connectors to return to original setup.

Hope the wiring explanation helps for 'ya.

Yeah it did thanks heaps Iet you know how it goes

And what's the ratio for on the sheet? Just do 1km on the odometer and GPS and then find the percentage of the inaccuracies and find that on the sheet and make it 10010101110 or what ever it is

Originally Posted by AK83

I can't say for sure, but I'm thinking No!

As I read this tute, he's saying that there are 3 wires on the SCU. Is that right?

If not, didn't it come with a install diagram/instructions?


On your drawing, you have brown wire connected to the cut pink/green wire out of the SLABS.
PeterM says to connect the white wire from the SCU to the cut Pink/Green wire coming from the SLABS.

The other end of the SLABS cut wire(going to the speedo) requires the green wire from the SCU.

This is according to PeterM's tute.

I've told my brother to get one of these for many years now .. stupidly(but not entirely wastedly) he got a speedo corrector from Jaycar.
Stupidly! .. we can confirm that it doesn't work. Not wasted effort, we did confirm that it doesn't work .. so no one else has to waste their $s to confirm this now.

Anyhow, we did connect it up and even tho I said it doesn't work .. not entirely true. It partially worked, just not very well.

But, for the C-6100 you need to connect it's wires thus:

Red = ignition
Black = ground
Brown = nothing!!
White = cut pick/green wire still in the SLABS plug(ie. to SLABS) Hopefully you used connectors on the wire ends.
Blue(or Green) = to other end of cut wire (leading away from SLABS/plug, which goes to speedo)

note on the blue/green anomaly. PeterM says in his tute that there is a green wire, seems you have a blue wire on your C-6100. What I've found that on the C-6100 there have been both colours .. both = ouput signal to the speedo.

What we did on bro's is to hook up onto cut wires a male/female spade connectors. red or blue types both work equally well(for the cable size). This way you can remove SCU at any time, and reconnect spade connectors to return to original setup.

Hope the wiring explanation helps for 'ya.

Sorry can't help at all with the ratio end of info.

The Jaycar unit didn't have that system, it used a small internal screw thing that you clicked up to a point, and measured.
If not enough, you opened the case and flicked some dip switches and did test again.

I'm emailing bro again to get him to get one for us to do it on his again .. this time properly.

What kind of speed error are you seeing?

eg. are you getting 90K/h indicated on speedo at 100K/h

I've found the ratio sheet, so I'm guessing:

if you get 90k/h on speedo at 100 k/h .. then we say you're 10% out.

According to ratio sheet, you need to up the output by 10%
C-6100 offer a 9.6% or 11.1% ratio change.

I would try 11.1% myself .. but you may want something else.

So I would try 00010010 on the dip switches(which would give me 10% more on the output side).

But if you wanted to use the 9.60% ratio instead, then you would use 10010010 on the switch.
IIRC, you have 285's on your rims? So your ratio change would be higher I guess.

Reminder, I don't have experience with this system, but this is how I read the ratio sheet.

And I prefer a small bit of headroom on the speedo .. sometimes you forget. So 1k/h over is more helpful. And in the end 1 k/h difference is totally undetectable anyhow.
But if you used the 9.60% ratio, it could show 99 at a road speed of 100, so whilst your sitting on the usual 'dollar-three', you could be at a real ... point losing/wallet lightening ... road speed of a dollar-four!

You have a manual, but if anyone with an auto can advise if the ratio correction helped in taming the auto on changes(primarily 2-3) and torque converter lockup at 80.
Or are those trans parameters coming directly out of the SLABS, so before the SCU.

Originally Posted by Kaaaiju

Hi, sorry about this very crap drawing, so what i have done is the right way? I read the online tutorial by sunnie but the last part i dont really understand (sorry) as it doesn't mention any specific colors to the SCU.

Any help will be fanastic

I’ll post my drawings - give me an hour or so

Originally Posted by Kaaaiju

Hi, sorry about this very crap drawing, so what i have done is the right way? I read the online tutorial by sunnie but the last part i dont really understand (sorry) as it doesn't mention any specific colors to the SCU.

Any help will be fanastic

I followed Slunnie's tutorial and those from Hunter DI and here's how I did it. If you don't have ACE (Active Cornering Enhancement) you wont need the green "jumper" wire. FYI Header 0290 in the schematic routes the RSS ie Road speed Signal to other functions that use it like the instrument pack, cruise control and ACE..... you got it right
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