2008 6.0L O2 Sensor Issue P1153 (New O2 Upstream Passenger Sensor 2 Bank 1 wonky voltage)

[SNES Avalanche]

Hey all,

Need some help as my inspection is due.

I've been getting an intermittent P1153 code indicating my upstream O2 Upstream Passenger Sensor 2 Bank 1 was going out so I replaced it with a new AC Delco unit.

After replacement I'm seeing the same issues and when I do a voltage scan it's all over the place.

Does anyone have a guide / wiring diagram so I can check the actual harness?

Driver side upstream left. Passenger side upstream right

 

[Fless]

Does the "B1" designator indicate Bank 1? If so, those are graphs of the driver's side sensors.

The O2S1 voltage should actively move between 100mV and 900mV, depending on lean/rich condition. Normal.

 

[SNES Avalanche]

Does the "B1" designator indicate Bank 1? If so, those are graphs of the driver's side sensors.

The O2S1 voltage should actively move between 100mV and 900mV, depending on lean/rich condition. Normal.

These are two upstream sensors.

Left is driver side S1B1 which is working S2B1 is the issue.

 

[Geotrash]

These are two upstream sensors.

Left is driver side S1B1 which is working S2B1 is the issue.

Are you 100% sure? What software are you using?

I also read this the same way @Fless did. And I also agree with him that what you're seeing in S1B1 is normal for the upstream sensor as the ECM adjusts the AFR on an ongoing basis. The diagram on the right also looks normal for a downstream sensor to me because the catalytic converter stabilizes the exhaust gas contents.

To answer your original question though, all I have for diagrams is for a 2012 Yukon XL Denali. Hope it's helpful.

 

[SNES Avalanche]

Are you 100% sure? What software are you using?

I also read this the same way @Fless did. And I also agree with him that what you're seeing in S1B1 is normal for the upstream sensor as the ECM adjusts the AFR on an ongoing basis. The diagram on the right also looks normal for a downstream sensor to me because the catalytic converter stabilizes the exhaust gas contents.

To answer your original question though, all I have for diagrams is for a 2012 Yukon XL Denali. Hope it's helpful.

View attachment 411673

Thank you for the diagram!

The photo is a comparison of the two upstream O2 sensors the app just names them funny. Left is Bank 1 S 1 right is Bank 2 S 1.

Bank 2 is also unable to report on a short term fuel trim.

 

[Geotrash]

Bank 2 is also unable to report on a short term fuel trim.

Ah! Given that, I suppose that the problem could be anywhere between the OBD port *and* the O2 sensors on the pax side of the engine, and possibly the ECU itself.

FWIW, we've had a number of people lately who've discovered weak grounds on the pax side - specifically the ground point on the front of the pax side cylinder head - impacting various systems with various codes and symptoms. You may want to look that one over real good, along with any other ground points in the vicinity.

 

[Fless]

You could also swap sensors side to side to see if the problem follows that move. Perhaps do that to rule it out.

Also, test the 12v feed with a good ground.

Lastly, test the heater circuit (check fuse first) at the connector for current passing capability with a heavier test light, like a bulb that draws 1A. The heater circuit is perhaps not likely an issue since it would throw a code for that. Again, a test to rule out that cause.

Not sure if this would help but it might give you an idea or two: