How to read AutoXray scanner

[tabahr]

I just scanned my 97 Chevy Blazer and got the following:

P0141
O2 Sensor
Heater Circuit
Malfunction
Bank 1 Sensor 2

Which sensor is that?? It is not like they are labeled?! How do I know which one to replace?

Bank 1 Sensor 2 is meaningless to me.

[Joe 1320]

Bank one is the driver's side, bank two is the passenger side. Sensor one would be the main 02 sensor located just above the manifold to headpipe union. Those are responsiable for monitoring the a/f mixture. Sensor two is located just after the cat and those are responsible for monitoring the effeciency of the cats. Before you start replacing them, pull the harness connector and spray electrical contact cleaner in the connections and reassemble. Bank 2 sensors, because of their proximity to under the chassis the connections are subject to much more road debris and crud contamination. I've seen these connections foul many times and a simple cleaning often fixes the problem.

[RangerBob]

Originally posted by Joe 1320
Bank one is the driver's side, bank one is the passenger side.

Huh?

[Joe 1320]

OK, so I typed it this morning before I had coffee. I fixed it.

[tabahr]

Thanks for the expertise! I'm gunna get under there and check it out. Funny though, the SES light was on for 2 days strait, but hasn't come on yet today.

[Injuneer]

Do what Joe told you to do. The problem is in the "heater circuit" or heater "element", not the sensing element. If it was a fuse, you would have the code on several sensors. Its a wiring problem, and intermitternt...... ergo - check the harness connector. Should be getting +12V from one of the fuses in the underhood panel to the brown wire in the harness connctor (key "on"). You should have a good ground to the black wire in the harness connector. If you have a good, solid circuit, then it might indicate a failing heater element in the sensor itself.