I'm converting the 1 wire 02 Sensor to 3 wire heated Sensor on my 350 TBI and i'm trying to figure out how to wire it. I'm installing a Bosch 3 wire for a 1995 V-6 S-10 chevy, read that was the one to use. The Sensor has two white wires and one black. On the three way connector it is marked A & B for the white wires and C for the black wire. I know one hooks to the wire from the ECM, one to a 12V hot wire and one to the ground. Anyone ever used a Bosch 3 wire Sensor? Which wire hooks where? Your help would be appreciated. Read a lot of posted threads for this subject, no help. Thanks.

 

Just did this on my 89 RS. I bought a 3-wire weatherpack connector for it, I forget the part number off-hand but it is a Dorman product found in the HELP! line. The black wire connects to the ECM and the 2 white wires are for the heater, polarity doesn't matter. I connected one to the pink/black (switched 12V)wire to my fuel pump relay and the other to ground.

 

Thanks Al. That easied my mind a lot. I had a thought that was the way it was hooked up, but wasn't sure and didn't want to roast a $50.00 Sensor. Thanks a lot, I'll order the female connector tomorrow.Later.