Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Are this diagrams the same for STI models? Sorry for the ignorance if they are but better safe than sorry.

Regards,

GS

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

STI is here

http://www.aquamist.co.uk/vbulletin/...ead.php?t=1711

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Hi Richard woukd the 08 diagram work for EDM? if not, do you have the EDM diagram? Thanks

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

I am not sure, try matching one of the above ECU physically. The fuel injector wires tend to have a pink trace on it. This will give you a good clue.

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Hi, I have a question about 03 usdm, more precisely about amber and white ecu harness connection. If I understand right, I should cut *24 cable from ecu (black&white in my case), connect white cable to part going to ecu and amber to rest? I have HFS-V3, if it's of any importance..

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Like to confirm you are referring to the brown cable rather than amber?

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Yes, that one. And whole that "CUT&SPLICE" part in red circle on the diagram

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

OK. it is a white and a brown wire from the grey harness. It is just a relay contact, goes open circuit when failsafe is triggered.

You need to cut the B&W wire in half. Connect the "ECU-side" to the white wire and the "BCV-side" to the brown wire.

To avoid CEL, link DR1 on the circuit board

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Richard, is this wiring diagrams applicable to the 2013 usdm wrx or did the pinout change at the ECU after 2009?

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

I need to update the HFS3v3 soon. Meanwhile, you can use the wiring diagram below:

http://www.aquamist.co.uk/vbulletin/...ead.php?t=2189

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

Sorry to bring this back from the dead, but why cut boost and signal ECU? Can the ECU not do both? Just wondering...

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

It wasn't clear, apologies, it was meant to be either/or.

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

I had a short and an rechecking the wiring. The wiring of this diagram doesnt agree with the WRX ECU. I just measured current on each of the partially pink injector wires and all of them have a (+) signal, while your green wire states that it requires a (-) signal from the injector.

http://www.innovatemotorsports.com/r...ru_Impreza.php

This shows the same thing.

So is the polarity OK? Because I'm pretty sure most of the WRX if not all Impreza have a common ground and only "speed" (+) outputs to the ECU from their Injectors.

Re: Subaru WRX to HFS-3 wiring diagrams (2002-2009)
 

There is nothing wrong with either diagrams.