: 954x1412 px
: July 2, 2018
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.
Heat can also decrease a battery's lifespan significantly. Hot weather causes liquids inside batteries to evaporate as well as internal damage. This can occur whether you are driving or if the car is parked. The magazine recommends that vehicle owners in hotter parts of the country have their car battery tested after two years of ownership and then every year after. Those who live in colder areas can wait four years after buying a car to test performance and capacity, then every year after.