: 1297x1953 px
: June 25, 2018
Vehicle charging systems haven't changed much over the last few decades. But with the increasing complexity of the modern automobile, along with the addition of many aftermarket accessories such as cell phones, DVD players, high-power audio systems, alarms etc., the role of the charging system is now more important than ever. The charging system on your vehicle can be thought of as a small power plant which does exactly what its name implies - charges and maintains a good state of charge on the battery.
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.