Turbine speed sensor

[perezsaturino]

I have a 07 Subaru legacy gt turbo limited 2.5 when I put the scanner on it, it coded p0715 or turbine speed sensor. Changed out the harness an speed sensors but it keeps going into limp mode. I don't know what else it can be. any suggestions.

 

[Ecmbuster]

And the transmission is a 4EAT or 5EAT? The description is for turbine speed sensor 1 or 2?

 

[perezsaturino]

It's the 5EAT and not sure but I replace the complete harness.

 

[Ecmbuster]

Measure speed sensor 1 and speed sensor 2 with Free SSM and an oscilloscope.

Free SSM 1.2.5 is PC based and working on older Subaru models without CAN, only K-Line.
Works with XP, Windows 7 and Windows 10. The application will access SSM full Engine and Transmission diagnostics.
Link: https://sourceforge.net/projects/freessm.berlios/files/latest/download
USB Cables used:
VAG-K + CAN USB (at times called KKL or K plus CAN)
OR (FTDI) FT232BL USB
Examples of operation:

Subaru FreeSSM – Complete DIY ECU and TCM Management | AutoInstruct

We show you how to use FreeSSM, a complete DIY tool for ECU and TCM Management of your Subaru vehicle. It provides access to the ECU and TCM for Legacy, Liberty, Outback, Baja, Impreza, Forester and Tribeca models of MY1999 or greater.

www.autoinstruct.com.au

The oscilloscope will measure a square wave and increase the cycles as RPM increases

https://www.researchgate.net/figure/Square-wave-signal-from-the-function-generator-displayed-using-the-maximum-time_fig4_30498875

Speed Sensor 1 is mounted at the front of the transmission, close to the mating surfaces of the engine and transmission.
This site also describes the location:

DIY 5EAT AT Turbine Speed Sensor 1 Replacement P0715

Welcome to the (self-proclaimed) BEST guide for replacing the AT Turbine Speed Sensor 1 for the 5EAT automatic transmissions. If you have found your way here, you are probably praying to the seven sisters that this will fix your problem. Keep reading to find out if this is for you...

www.subaruoutback.org

My oscilloscope and test equipment measures what has been described.

 

[Madd]

I have a 07 Subaru legacy gt turbo limited 2.5 when I put the scanner on it, it coded p0715 or turbine speed sensor. Changed out the harness an speed sensors but it keeps going into limp mode. I don't know what else it can be. any suggestions.

Did you figure out what the issue was?