what does these 2 code definitions mean? on 2011 Buick Regal

Catalyst System Bank 1 Low Efficiency and HO2S-11 (Bank 1 Sensor 1) Circuit Low Input Thanks in advance for any help given.

by in Kimberly, AL on February 12, 2014
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3 answers
ANSWER by , February 12, 2014
You gotta check out the o2 sensor output + wiring etc on bank 1 Google it of utube tell you how to go about it..
ANSWER by , February 13, 2014
check with the dealer could be still under warranty
ANSWER by , February 13, 2014
warranty on emissions is 7yr 70k miles