: 1772x1181 px
: June 23, 2018
When you pop the hood and look at the complicated mechanical devices called engines, you notice right away there's plenty of wiring. In fact, the wires seem to snake around the engine in a complex configuration that makes little sense to anyone who is not a mechanic. Auto engines have plenty of electrical configurations that are critical to their smooth operation. The fact is that when a car experiences problems, it could easily be an electrical problem as much as it could be a mechanical problem. Any qualified mechanic needs to be familiar with both mechanical and electrical problems in order to be efficient at his or her job. That means a mobile car mechanic must be prepared to complete a variety of repairs including those related to the electrical systems.
The test procedure is quite simple. Set the meter to read DC volts, and set the correct range if needed. Some meters will select the correct range automatically. Nearly all meters will come with instructions on how to set them to read DC volts. Next, connect the meter across the vehicle battery, positive (+) to positive (+) and negative (-) to negative (-). With the engine running at a moderate idle - say 1200 to 1500 RPM, the meter should read approximately 13.8 to 14.8 volts and be steady. If the reading is substantially outside these figures and all other items mentioned have been tested and verified good, then the alternator is likely defective.