This code showed up recently and I am wondering if anyone else has experienced this same thing. I know the code refers to the bank 1 sensor 2 O2 sensor but I swapped the one from the other side and still get the error code from the replaced sensor so that rules out the sensor being faulty. Also checked the fuse for the heater circuit for the sensor and no problem there either. Checked the connectors on all the wiring harness connections and found no bent or bad pins also no problem with the O2 connectors either. I can delete code with my scanner and then start car and drive with no code reappearing. Only when I shut car off and restart does the code reappear and not always right away it may take a few minutes to do so. Car is not under warranty as it had minor engine fire when I bought it. Replaced the complete engine wiring harness (it is new) and some plastic items. No fire damage to the fuse box or other electrical components fire damage was mostly on the driver side around brake booster. Replaced wiring harness because the wires on that side were all burnt or melted. Cars runs fine other than the check engine code.

Any thoughts or suggestions?

Possibly a wire past or on the new wiring harness rubbing on metal causing a ground fault? I don't know, I'm just guessing. Best bet is to start tracing wires or get a ground fault finder at somewhere like Harbor Freight. And find it that way.

Are you sure the warranty is blocked?

It may have a salvage title. Thats probably why gm won't do anything with warranty. I bought a jeep with salvage title about 12 years ago. It was a stolen and trashed, Chrysler voided the warranty because of the salvage title. I think all the car companies void the warranty for salvage titles.