The other day my truck ses light came on got it scanned and it was a code Po 141 oxygen sensor heater malfunction bank 1 sensor 2....so i checked the wiring and it looked good so i replaced the sensor with a bosch brand one, well about 4 days later I have a code po 137 bank 1 sensor 2 low voltage, so what can be wrong now ?? The truck is a 1997 chevy k1500 with the vortec 350 with no mods yet thanks for any help