Check Engine Light: Codes Thrown

2009 4L6 check engine light came on as I was haul in some bathroom Reno materials. I ran the codes (P0161 02 Sensor Heater Circuit Bank 2 Sensor 2 & C1201A Engine Control System Malfunction) each one has a couple dozen what if’s. I did have some work done a a year ago, IDK if it’s related but before I take it back to my mechanic any thoughts?

 

The C1201 will set any time the check engine light is on so disregard that until the engine code is fixed, it should self clear after.

The P0161 is likely a bad heater in the Bank 2 Sensor 2 O2 sensor but it could also be a wiring issue or very rarely a bad ECM.