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Confirmation Test (Using Oscilloscope)

  1. To test banks No. 1 and No. 2 oxygen sensors No. 1, backprobing, connect oscilloscope between ECM E16 connector terminal No. 17 (White/Red wire - ground) and terminals No. 12 (White wire) and No. 11 (Black wire). To test banks No. 1 and No. 2 oxygen sensors No. 2, backprobing, connect oscilloscope, between ECM E16 connector terminal No. No. 17 (White/Red wire - ground) and ECM E18 connector terminals No. 18 (Red/Blue wire) and No. 27 (Green wire).
  2. Ensure all accessories are turned off. Start and warm engine to normal operating temperature. Increase engine speed to 2500-3000 RPM for 3 minutes. Using oscilloscope, ensure heated oxygen sensor (banks 1 and 2 sensor 1 and 2) feedback to ECM fluctuates around .5 volt and banks are different from each other. See Figure.
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