Originally Posted by DarkiSt
Alex, I have a '03 JDM Legacy GT that's giving the same P0031 (HO2S Heater Control Circuit Low - Bank1 Sensor1). Did you figure out if the USDM sensor will work? I'm seeing a Bosch 02 sensor on eBay for us$31 that says it fits all trim models but I don't know if it'll work for the JDM models.
Hey! I didn't get the chance to test a USDM O2 sensor and see if it works on JDM cars...
In the end i went with this: ( http://japanparts.com/db/parts_detai...&SEARCH_page=3
) replaced the faulty sensor and since then the "check engine" light is off and the car is working fine.
This was the cheapest Subaru Genuine O2 sensor that i could find in the net.
The Subaru dealership in Cyprus wanted around 250 Euros for the same part!!!
Hope this helps!