Handbook 652 Body Electrical Diagnosis Principles of The first step in effectively diagnosing electrical problems is to have a good understanding of basic electrical principles. These concepts were covered in depth in the 623 course. In this course, we will review each concept, emphasizing how they are applied on the car when diagnosing an electrical problem. Electricity Voltage Simply put, think of voltage as electrical pressure or pressure differential. The difference in pressure that makes a hydraulic pump work applies similarly to electricity.
The pressure differential created between the positive and negative terminals of the battery causes the electrons in a conductor to move when the two terminals are connected. This movement or flow of electrons performs useful work. Whenever work is done, pressure is used up. We can measure where work is done in an electrical circuit by measuring where voltage is used up. Technical Training 17