P1103 Buick HO2S Heating Circuit Bank 1 Sensor 1 Voltage Too Low

P1104 Buick HO2S12 Sensor Circuit Voltage Too Low Air Leak

Possible causes
– Faulty HO2S12 Sensor
– Exhaust leak near HO2S12 Sensor
– HO2S12 Sensor harness is open or shorted
– HO2S12 Sensor circuit poor electrical connection
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
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