: ACDelco O2 Sensors

09-11-12, 01:48 AM
I have a DTS 2006. I always get the code P0154 on my OBD-II scanner which means "Bank 2 Sensor 1 No Activity Circuit"
I am to replace the sensor with a new ACDelco Oxy sensor. However, ACDelco obviously has different application terms. In their online catalog they have the following:
1. Heated Oxygen Sensor (Position 1)
2. Heated Oxygen Sensor (Position 2)


I wonder which one of the two is meant to be Bank 2 Sensor 1 ?
Position 1 or Position 2 ?!


09-15-12, 12:37 AM
The one that is listed as position one (prior to the cat. converter). I think the only difference would be the length of the wiring on the sensor. No activity could mean no voltage thru the harness to report back to the ECU. You might have an open connection rather than a faulty sensor. Oxy sensors generally get lazy, slow to respond, over time. Rarely do they electrically fail to work at all. The codes never tell you what part to replace. They allow you to check that circuit/ harness and confirm a wiring problem vs. a component failure. If you replace it, you might now have a good spare one!

09-15-12, 02:53 PM
Bank 1 is the right (firewall) side, cylinders 1-3-5-7, O2 sensor in the top of the exhaust manifold is B1S1
Bank 2 is the left (front) SIDE, CYLINDERS 2-4-6-8, O2 sensor in the exhaust manifold collector is B2S1
There is an after-cat O2 sensor, B1S2.

Some models had a pre-cat sensor also, so that right bank/exhaust pipe sequence is B1S1, B1S2, B1S3.