TBITrucker

I am switching to a 4 wire O2, a delco AFS75. I lost the page I bookmarked with the wiring. I searched here but the posts I found were not what I needed

I have 4 wires and I only figured out 2! (I think)

Wire A is Tan ( is this the O2 signal to the ecm?)

Wire B is Purple ( is this the high current ground for the heater?)

( One of the above goes to the original single wire from the stock O2 and the other to ground I think)

Wire C is Black and goes to ground ( Right?)

Wire D is Brown and goes to +12v when the ignition is on (Right?)

I guess I need to know what all 4 wires are just to be safe.
I don't want to hook my meter to it because I read you can damage the sensor by grounding or applying voltage to the output wire and I'm not sure what one that is.

Thanks!

rhomanski

The purple wire is the sensor wire to the computer if i remember right.I put a three wire on mine so the other two were power and ground for the heater.Hope this helps.

TBITrucker

Thanks I guess I had a few mixed up

Can anyone else verify this?

Apeiron

Brown is the heater power.
Black is the heater ground.
Purple is the sensor signal.
Tan is the sensor ground.

TBITrucker

Now off to the bone yard for a 4 wire conector, and whatever else I can stuff into my pockets!