99 V70....AFR sensor or O2 sensor

[JoeNewbie]

Which does my car use?? An AFR or O2 sensor.........I'm leaning towards AFR do to the blue signal wire and the output voltages.......The ECU keeps a constant voltage on the sensor........

[MadeInJapan]

Your car uses an 02 sensor to sense the air/fuel ratio.

[JoeNewbie]

MadeInJapan,
I've just learned my car uses a AFR sensor.....Not an O2 sensor. Although I, and Volvo, and anybody selling the part, will still refer to it as an O2 sensor. Technically it is an ARF sensor. Most notably by the blue signal wire, and the fact that it is a current based device, and not voltage based.
Although the voltages do vary, the do so in the ranges mentioned in the doc below. When an "O2" sensor goes rich, voltage goes high. When a "AFR" sensor goes rich, voltage goes low......And so on........I ran all the tests on my own sensor and verified it with the Volvo shop.
This is the information I was looking for when I originally posted this.....
Please read.............
http://www.autoshop101.com/forms/h37.pdf

[MadeInJapan]

Thank you...I went with the fact that we have 02 sensors...it's good to learn something new every day. Thanks for the correction.