3. technician a says that on-board self-diagnostics test mode procedures should be conducted on a cold engine. technician b says that many diagnostic trouble codes (dtcs) will monitor items only when the engine control system is in closed loop.

Technician B

Explanation:

on-board self-diagnostics test mode procedures should be conducted on a warm engine since many DTCs only monitor in closed loop. Therefore, technician A is wrong. Many DTCs will monitor items only when the engine control system is in closed loop. Closed loop operation requires the engine to reach a certain operating temperature before it can be entered. Therefore, technician B is correct.

answer:

science is the study of the nature and behavior of natural things and the knowledge that we obtain about them. a science is a particular branch of science such as physics, chemistry, or biology. physics is the best example of a science which has developed strong, abstract theories.

pseudoscience is a collection of beliefs or practices mistakenly regarded as being based on scientific method.

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