Webyour alternator should be inspected and the belt should be replaced regularly as specified by the manufacturer. Your napa autopro technician will test and install an alternator that meets your manufacturer’s specifications. Webto test if your alternator is bad you will need to perform a test with either a voltmeter or a multimeter. If you use a multimeter you will need to set it at dc volts to measure the. Webdec 18, 2023 · use a multimeter or battery tester to confirm whether your battery is above 12. 4 v or not. If the voltage is low, charge your battery with a battery charger or jump. Webhere are two tests you can also use to determine the route of your alternator repair: For an accurate measurement of your charging system’s voltage, attach. If no manufacturing defect is found,.