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Ground 02 bias voltage

  • autojoe
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5 years 1 month ago #41863 by autojoe
Ground 02 bias voltage was created by autojoe
Watched a video Burnie Thompson ats he was working on a 2012 gmc terrain 2.4 l engine. He stated 02 ground bias on this vehicle supposed to be 1.25 volts on 02 ground. It has a convential 4 wire heated 02 sensor. Vehicle had a lower ground bias. Had a code p0171. Ending up being a faulty pcm. Great video. I have always seen 450mv on signal wire. Does anyone know if newer gms using ground bias plus 450mv on signal?

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  • VegasJAK
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5 years 1 month ago #41869 by VegasJAK
Replied by VegasJAK on topic Ground 02 bias voltage
can you provide a link to the video? would like to see it. thanks
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does

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  • Noah
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5 years 1 month ago #41873 by Noah
Replied by Noah on topic Ground 02 bias voltage
Must be this one.
"Ground cannot be checked with a 10mm socket"

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5 years 1 month ago #41875 by autojoe
Replied by autojoe on topic Ground 02 bias voltage
That's the one. Any ideas?

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5 years 1 month ago #41876 by Noah
Replied by Noah on topic Ground 02 bias voltage
I found this by searching the flow charts for oxygen sensor codes. I didn't know about that either, but my shop hasn't seen many cars of that vintage until fairly recently.

"Ground cannot be checked with a 10mm socket"
Attachments:

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5 years 1 month ago #41884 by autojoe
Replied by autojoe on topic Ground 02 bias voltage
Bernie shows tan/white should have a bias voltage of 1.25 volts or the 1.27 volts. Wonder if the 02 signal wire has a bias also and the voltage amount.

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5 years 1 month ago #41888 by autojoe
Replied by autojoe on topic Ground 02 bias voltage
I imagine just a ground bias.

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