Code P0140

I was on my way home yesterday and SES light came on, stayed on solid. I stopped by local Advance Auto to have code read and P0140 came up. Something about O2 sensor circuit- no activity detected (Bank 1 Sensor 2). Thought I'd check in with you guys for assistance. Car has 149,000 miles on it. Front sensor was replaced about 5-6 weeks ago but rear O2 is still original.

Check the wiring on the sensor to make sure it didn't burn through. Since you have 149K
on the clock go ahead and replace the rear sensor regardless. I suspect that the sensor is bad and that is why it set the code.

Replaced the rear O2 this morning. Here is a pic of the the old one.

I'd say that it has seen its last exhaust pipe. Appears to be in very bad shape so changing it will probably solve the issue.