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Information About Rb25 Automatic Transmisson

reebdreworx
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reebdreworx Newbie

reebdreworx

Posted
Posted

Hi Forum,

I need to know what information a RB25DE 5-Speed AT Gearbox management ans the ECU are Exchanging. I already look on the wires. Two of them have a sqarewave signal and on the other signal is some noise I don´t understand. The things I guess these both ones are exchanging are ignition cut for gearchange and some diagnosis data. So I´m searching for all information about it I can get. Maybe you guys can help me. That would be awsome.

Now the part why I need this Information. I want to hook up a RB25DE 5-Speed AT to a RB26DETT ECU :-). Because the RB26DETT some much more cool features.

The engine will be a RB25DE that is modified to be a RB25DET including the piston cooling.

Regards Alex

the stink Explorer

the stink

Posted
Posted

I hooked up a datalogger to my 4 speed auto in my R33 and found 4 wires of interest

Pin56 - Throttle position sensor signal to gbox (variable voltage)

Pin5 - Was some sort of decelleration signal that seemed to trigger when decelleration was above a certain level. Signal from gbox to main ecu (goes low on activation)

Pin 14 - Power upshift signal which activated on 1-2 or 2-3 upshifts at high throttle. From gbox to main ECU (goes low on activation)

Pin 15 - Was some sort of acceleration signal that seemed to trigger above a certain throttle position but this varied a little. Main ecu to gbox (goes high on activation)

Might be similar in the 5 speeds but i don't know for sure...

I would be interested to find out more about what is happening in the computers but there doesn't appear to be much info around.

neil

  • 1 year later...
Cold_Fusion Rookie

Cold_Fusion

Posted
Posted

Well I must say i am after similar info (which I also can't seem to find on the net). My R32 5 speed auto is really on its way out. Prob never looked after from the start and I want to fit in a R33 DET 4 speed (3 + O/D for the purists) with the associated gearbox ECU but I wonder if it is straight forward. Are the signals all going one way? i.e. from engine ECU to gearbox ECU.

Essentially I'd like to know if I can get the R32 RB25DE ECU to operate the R33 RB25DET gearbox ECU without hiccups. Thanks for your opinions :laugh:

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