How To Check If An Alternator Is Bad. If you have a newer battery but your car wont start you may have a bad alternator. Testing the Alternator and the Battery for an Answer.
Your voltmeter should read 0. While running the car note the brightness of the interior lights. The vehicles whether its your car or a customers car instrument cluster has the battery light on.
If you can jumpstart your car and it stays running chances are youre dealing with a bad battery.
An illuminated dashboard light can indicate a problem with an automobile charging system. To check for a possible bad alternator diode switch your voltmeter to a low setting on the AC alternating current voltage scale. This is really obvious when headlights are on at. Have a Professional Test the Alternator with Dedicated Equipment.
