4runner 1995
I have 4 wires,

Blue - ?
White - ?
2 Black - these are probably heater conection

Which one is signal?
Which one is mass?
I need to conect new sensor but wire colors are different

 

now a reply for my own post :p

Blue wire is signal
White one is mass
2 Black sensor heating

 

Going through this myself right now...just curious as to what you mean by "White one is mass"?


Thank you for the post, BTW.

 

if your replacing it with a bosch the two black wires (stock) will go to the two white ones (bosch), no polarity so it dont matter which way you hook it up. The blue one (stock) will go to black (bosch) and the white wire (stock) will go to the gray wire (bosch)

 

I have a factory O2 sensor (BLU, WHT, BLK, BLK) and a truck from some dumb-a that cut the plug off the truck-side of the wiring harness... (BLK, BRN, WHT/RED, PNK/GRN).

 

i found your answer sir


The pink/green might be tan/green and the yellow/red might be white/red, my crap is probably just old and faded

 

Thank you for the pic, I appreciate your follow-up and I'm sure the next guy will too.

I've actually had it hooked up for a couple days now and I was able to get the info to hook it up right after searching here for a while.

 

wow, wierd, my Bosch was easy to install... it plugged right in

I tried one of the universal ones like that first, but it didn't want to work for me, so I just got a direct replacement

 

I'm guessing that mass means ground since the white is the ground wire.

 

And if you're using a universal sensor, there's always the wiring diagram that comes in the box....

 

he was asking about the truck side of the plug (pink, brown, yellow, black). the instructions that come in the box, Bosch at least, refers to the colored wires on the O2 side of the plug (blue, white, black, black)