Countershaft VSS on PNF Civic Si K-Pro v4

[J1000]

Hello all,
I have just completed a swap into my 2005 EP3. I swapped a k20z3 and 6spd transmission from 07 Civic Si. All is working great except the VSS.

Originally I used a Dakota Digital VSS converter to convert the signal and that worked, however when launching hard from a stop the VSS signal would not register until some time later when the vehicle was up to speed. Bad for autocross unless I disable the vtec minimum speed which I guess is an ok work around.

To remedy this my idea was to check the box in the ECU for a countershaft 05+ VSS and then use my converter box only for the dashboard speedometer. However, it appears my ECU does not recognize the VSS signal straight from the sensor. I have all of the stock wiring in place and I rewired the plug for the VSS so it is all correctly wired and the Dakota box is not wired in at the moment. The ECU is just showing 0 VSS.

This topic has been beaten to death but I have not seen this particular setup covered (using 05+ VSS for ECU and converter for speedo).

I thought I read something about needing to solder a jumper into the ECU to allow the 05+ VSS to be read on a Civic PNF ECU, is that accurate?

Any help would be greatly appreciated I will provide any information requested.

Thanks

[J1000]

I can't seem to edit the above post but here's more info

- 2005 Honda Civic Si
- K-Pro v4
- 37820-PNF-A13 354468-4914
- 4.5.6
- PRB calibration
- K-Pro purchased through Kseriesparts.com 6/13/18

[J1000]

Calibration attached.

[Spunkster]

If you have a converter it must be wired so that it sends the same signal to the ECU and to the dash. The ECU cannot alter the dash reading in any way.

[J1000]

Hello thanks for your reply.

I am not trying to have the ECU modify any signal.

I am trying to get the ECU to read the 05+ countershaft driven VSS

It doesn't read the signal at all.

Any help you can provide will be greatly appreciated. Thank you.

[Spunkster]

You cant use the converter and set it to countershaft. It is one or the other, and the countershaft setting will not allow you to make any changes to the dash. It is best to just use the converter at this point.

[J1000]

Hi Spunkster. Thanks again for the reply.

Can you please ignore the converter and help me get my ECU to read the 05+ countershaft VSS?

Thank you

[Spunkster]

It uses the normal vss input and it will just adjust the signal read in the ECU. This will not have any effect on the dash.

[J1000]

It's not working.

[Spunkster]

With the VSS set to normal is it reading anything?

[J1000]

You cant use the converter and set it to countershaft.

Well I did it lol it's working 100%

[J1000]

VSS was working the whole time, just didn't realize the ECU had "VSS" and "VSS input" and I was looking at the wrong one. Just a hot tip for future reference, could have confirmed I was looking at the right signal on day 1

[J1000]

Anyone reading this in the future what I did was just put a diode inline with the VSS signal at the split. The VSS comes through the firewall and then there's a Y split and one half goes to the dash and the other to the ECU. I inserted a diode on each leg of the Y and one went straight to the ECU and the other went into the Dakota Digital Converter and then on to the dash.

Now everything works, but more importantly the ECU sees the raw VSS and therefore can register VSS during hard launches from a stop, burnouts, whatever and allows a functional launch control rev limiter and speed based VTEC activation.

In summary, Spunkster was wrong and nothing he said was in any way helpful.

https://youtu.be/uBR838WQqoA

[Kylerthecreator]

So to clarify, you are able to run high frequency signal to and 02-04 kpro? And make the proper adjustments to kpro to correct the signal? I don’t care about my dash working, just want my ecu to register speed. How did you go about wiring front the plug to the ecu?

[N/A.rsx]

Hello hondata thanks for the add. I was not sure where to post so i figured this section would be a good place. I have a lot of information so please bear with me.

Ecu-pnf 5speed Kpro v4

Custom harness- modeled after 02-04 rsx harness

05/06 transmission

I allready damaged my prb ecu and kpro I want to make sure this does not happen again. My tuner ask for rear speed sensor incorporated “hall sensor”into harness for launching the car instead of using factory vss. My wiring guy put a 3 wire dtm connector labeled rear speed “connected to main vss, with the signal wire from harness vss loose by the ecu” he also said that my stock vss is now 5v and sensor ground instead of it being 12v like 02-04.

What would be the best way to get vss reading in the ecu not worried about speedo cluster. It is a drag car. I just want to be able to use vss to launch car correctly.

I have a Hall effect speed sensor mounted in rear .30000 away from abs ring not wired up. I’m willing to go back to normal vss would really appreciate some solid advice so this does not happen again. Thank you!