Can someone tell me which wire does what for this rear o2 sensor on my evo x? I don't have access to a service manual so any help would be greatly appreciated!

I just need to know which one is the 12v, ground, and o2 sensor signal wires

 

Multi-meter.

The 12 v one is the one with 12 volts. The one that ohms out to ground is ground, and the one left is your signal wire.

 

Smart-*** response, but very very true..

 

haha, not a smart *** response at all...its totally true but unfortunately i dont have a multimeter, and dont know how to use one either....I'm just wondering if someone that has access to a service manual or knows what wire does what....

 

for the stock sensor (denso), it should be:

blue: signal+
white: signal-
black: heater
black: heater
(heater wires are not polarity dependent)

 

wait, so the white wire is sensor ground?

 

yes