High O2 bias voltage

I was doing some testing on a 2011 Equinox following procedures in the book. Car runs fine and scan data looks good, but the bias voltage on all O2 sensors when cold or disconnected is 1.9 volts. When running the scanner is showing going up and down between .04 and .09. When I connect to my scope the reading goes between 1.04 and .9. Something I’m doing wrong?

Should I be posting this in a different forum?

Ken

Warmed up and running properly, the O2 sensor output should oscillate, at least,  above 800 millivolts (0.8 volts) and below 200 millivolts (0.2 volts). Service information for this vehicle states "from approximately 40 mV to approximately 900 mV". Unplugged bias voltage on the signal wire should be 450 millivolts (0.45 volts).  Scan data should reflect this. I'm not sure what, if any, bias voltage should be on the Low Ref.

The readings you listed do not sound right, at all. Where, and how, are you connecting your meter/scope? 

bias voltage on all O2 sensors when cold or disconnected is 1.9 volts.

With an incandescent test-light connected to battery negative, can you pull this voltage to zero?

 

wrote:

Unplugged bias voltage on the signal wire should be 450 millivolts (0.45 volts).  Scan data should reflect this. I'm not sure what, if any, bias voltage should be on the Low Ref.


 

After reading jreardon's reply in the repair section,

The computer is sending out 2.9 volts on the signal wire and 1 volt on the ground wire.

I reserve the right to stand corrected.

Will retest and post.

Thanks