Silverado Kid

my 03 silverado had this p0135 error (heater sensor malfunction bank1 sensor1), so i switched the o2 sensor to bank2 just to confirm if the sensor was bad or the wiring and clear dtc. after the switched, the error went with the o2 i switched, it's now p0155 (haeter sensor malfunction bank2 sensor1). this confirmed that the o2 sensor was bad. so i replaced the supposed bad sensor1 in bank 2 and after 15 miles or so check engine light comes on again and still indicating the same error code p0155. i cleared dtc error again after a while it comes on again. i'm now stumped, i was wondering if someone can shed a little light on what might be the possible promlem is? oem sensorwas made bydenso and i replaced it with identical denso also (but part number from oem is different that what i installed which is 234-4668). any help is greatly appreciated.

ukrkoz

http://www.obd-codes.com/p0155

short in harness.