Do you need a multimeter to check your alternator?
Do you need a multimeter to check your alternator? A multimeter measures voltage as well as other electrical properties such as current and resistance. You want to measure voltage when you're checking your alternator. Check the battery first. The battery is needed to start the vehicle, which, in turn spins the alternator at sufficient speed to keep the battery charged. What should the voltage be on an alternator? Check the reading on the voltmeter again. The voltage should increase by between 0.5 and 2 volts to around 13.6 to 15.8. If the reading stays the same or drops, that means...