O2 sensor harness problem ?

[JackStraw1]

Ok so My CEL which had been intermittently coming on for the past 4 months finally came on and stayed on this past week. Checked the codes and got 33 and 34. O2 sensor and knock sensor. Then the O2 sensor code went away and just the knock sensor code kept popping. Not quite knowing what to make of this, I ran the Mode 1 and Mode 2 diagnostics. Absolutely no LED's at all. Not good.

 

So.... I began to run thru the testing algorithm for O2 sensor.

 

First I checked the voltage at terminal "c" with the ignition on ( I tested the female plug coming from the ECS ) - nothing - 0 volts

 

Then I checked the 15A fuses under the dash - all OK

 

Now it says to check continuity between the O2 sensor harness and the ignition switch - and I am confused as to how to do this. I know how to check continuity. I just can't figure out where. If I am reading the diagram right (and that's a big if folks) then the B/W wire is from the ignition and is the "a" terminal. Where is the continuity supposed to exist ? between "a" and "b" or "a" and "c" ?

 

Sure would appreciate any help here.

 

Thanks

[JackStraw1]

Sorry, I don't know how to post an image here but I am referring to the algorithm and diagrams in EF & EC -97 in the FSM.

Maybe someone else can post that up.

Thanks.