p0136 civic

ok so i tried getting my brothers civic inspected today and it failed because of the code p0136 (Oxygen O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2)). from what i researched the causes could be from #1 Faulty O2 sensor leak in exhaust close to O2 sensor. less than a year ago i installed a new bosh oxygen sensor.and today replaced every gasket on the exhaust. not thing this is the problem. #2 Short to voltage on O2 signal circuit. traced all the wires no cuts no exposed wire anywhere. #3 Open in circuit resistance caused by corrosion in connector. cleaned the connector and put some die electric grease in the connector. any input is greatly appreciated.

Is the sensor wired correctly?

yea it did not throw a code after i installed it untill now

Then start with the cheapest fix if you’ve troubleshot those three things. Grab a spark plug non-fouler and put it in the sensor hole and screw sensor into that. If light goes away you know it’s a bad sensor.