A 1996 C-1500 4.3 W manual trans came in today with a code P 0141 HO2S Heater Circuit Bank 1 Sensor 2. I slide under the truck to take a look a look and came out scratching my head. 4 O-2's, left, right, pre catalist, post catalist. My scanner (Snap-on) reads ... Login to read more.