O2 sensor signal wire
 

I'm trying to find out which wire is the signal wire on 4 wire O2 sensors.
I know its one of the black ones, but if any one could tell me the color of the wire on the harness side, I'd be grateful.

https://honda-tech.com/forums/images...s/emsmilep.gif I'd try to figure it out myself, but I'm not multimeter friendly, unfortunately...

BTW if it makes a diff, it's a stock D15 harness in a 92 Civ sedan (Exhaust Mani O2)

Tks https://honda-tech.com/forums/images/smilies/emwink.gif

Re: O2 sensor signal wire (Azelas)
 

well from hours of taking off all the black tape off my engine harness this is what I found out:
primary o2 sensor
Black/Yellow = ground? well it goes to the Big cap that leads to nowhere
Black/WHite = sensor heater control
Green/black = ground? well it goes to the Big cap that leads to nowhere
White = primary heated o2, sensor -1

Secondary o2 sensor
Black/yellow = ground? well it goes to the Big cap that leads to nowhere
Black/white = sensor heater control
Red/yellow = sensor ground
White/red = secondary heated o2, sensor -2

Re: O2 sensor signal wire (raidacaipo)
 

Cool, Thanks a bunch!
Exactly what I needed to know ! https://honda-tech.com/forums/images/smilies/emthup.gif