During the diagnostic test procedure for a Catalyst Efficiency code, a diagnostic scan tool is connected to the DLC with the vehicle at operating temperature, and the data screen displays the pre-catalyst oxygen sensor continually switching between 200 mV - 800 mV, while the post-catalyst oxygen sensor's output voltage stays relatively steady at 700 mV. Technician A says that the post-catalyst oxygen sensor is fixed rich and should be replaced. Technician B says that the oxygen sensor readings are both normal. Who is correct?

A. A only
B. B only
C. both A and B
D. neither A nor B


Answer: B

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The general engineering change elements, terminology, and techniques are similar among companies where the ASME standards are followed.

Answer the following statement true (T) or false (F)

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How many wall ties are needed for a brick wall 43' long and 10' tall if the spacing of ties is 24" x 16"?  Round the answer to the nearest whole number.

What will be an ideal response?

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