This vehicle has flagged codes:-
p0136 o2 sensor circuit malfunction bank 1 sensor 2
p0430 Cat system efficiency below threshold bank 2
below are some snapshots of pre and post sensors at idle and 2000rpm. I only have a 2 channel scope so have treated bank 1 and bank 2 seperatly.

above is bank 1 at idle

above is bank 1 at 2000 rpm

above is bank 2 at idle

above is bank 2 at 2000 rpm

The car has two seperate cats one for bank one one for bank 2.

Am I correct in thinking that the switching on the post cat sensor on bank one is causing the cat efficiency code?

any opinions of the voltage post cat?

any help appreciated, would like to fix this first time as parts are expensive