RB25 Nistune Vct not working :(

[kubus]

can anyone help me out please

i just got a nistune z32 ECU - to power up my RB25 ( s13 conversion ).

it works all fine - but the vct is not switching on

on stock ECU it does work - replacing it with z32 ECU - it does not........

what could be the cause ??


cheers guys.

[Matt]

Okay since its an S13 conversion, are you getting a speedo signal in? You wont get VCT operation without it

(view the consult digital registers 1,2,3) and montior the consult view to see if VCT activates

[kubus]

none of gearbox sensors are connected to the ecu.... hmmmmmm

so why it doesn't need the speed sensor to cut in with stock rb25det ecu ??

cheers mate - thanks for fast reply.

[Eric]

the ECU gets the speed signal from the speedometer/cluster...not directly from the gearbox.

[Torque]

I have a bit of experience with that VTC function.

On Z32 it is purely activated by load. (at least in the images I had a look at)
However there is a speed and temperature threshold for activation of the system.
(and also deactivation)

You can monitor the activation in Nistune (see if flag comes on)

I don't know anything about your conversion, but RB25 ECU gets it's speed from the tachometer.
(As Eric said)

If Nistune displays speed in the dashboard, everything is connected correctly.

[kubus]

cheers for that i got it first time - but it is not working.....

will connectr the speed to the gauge cluster - and than back to the ECU .

and do you know by any chance will it work with s13 gauges ??

cheers.

[Torque]

Hi!

What do you mean it is not working?
Do you have a speed reading in Nistune?

[kubus]

it is not reading - as it's not connected - will be doing this monday / tuesday

as it wasn't needed with stock rb25 ecu

now as i need it for vct to work - i'll have to reconnect it all - good thing i'll have the gauge cluster working

but the question is - WILL IT work with s13 gauge cluster ?? i mean i know it will read the speed - but is it ok - with the z32 ecu ??

[Matt]

Try it out and see how it goes. Cluster will put out square waves representing the speed signal

I've noticed that the speed input on my bench seems to vary with different ECUS. I suspect the pulses to the ECU sometimes differ but never really looked into it too closely

[kubus]

will do - some time this week.

will let you know what happens.

[Torque]

The tach signal is conditioned by the speedo and then routed to
the ECU (on RB25) where it is also routed to the HIACS system for steering.

I think it is a generally a good idea to let the ECU know if you're in motion or not

[PL]

SR20's use the same system. Differential signal (sine wave) goes from the speed sender in the gearbox, up to dash. In the dash it gets converted from a sine wave (which varies in both amplitude and frequency) to a TTL square wave which the ECU can read directly. It also divides the frequency by 8.

I do lots of wiring for SR20 conversions and the speed signal can be a real issue with some of them, so I've made up a little circuit to take the place of the OEM dash as most conversions use aftermarket speedos. The other Nissan ECU's I've tested all seem to use the same sort of signal.

http://www.plmsdevelopments.com/ssi.htm

PL

[kubus]

it is not working :(:(:(:(

the ECU is : A18-A30 MA0

and it is z32 tt

all is working, the speedo, nistune can see the speed etc etc

but it is not working - vtc is not comming up ( the selenoid is powered )

there is no negative coming out of the proper pin on the ECU :(:(:(

what is wrong with it ??

[Torque]

Hello ...

How did you test?

Could you post your VCT setting?
(Screenshot)

[kubus]

didn't make any changes to what comes str8 from the nistune files

file->open address file -> browse ->misc ->Z32_VG30_256_e_for_RB25.adr

Z32_FOR_RB25_41P03_MT_V2 as for the image file

or I do something wrong there ??

vtc selenoid min temp cut -50
vtc selenoid max temp cut 110
vtc RPM recover 6100
vtc RPM cut 5900
vtc selenoid TP 60
vtc selenoid max speed cut 10