How To Check If Alternator Is Faulty. First open the hood and start the car. The diodes are part of the rectifier assembly converting the alternators AC output to DC.
If you have a voltmeter you can check your battery voltage and terminal connections when the engine is running. Often youll see the red battery icon light stay on but you may also see a Check Engine or ALT indicator. PART 3 - Verifying that the alternator fuse in the fuse-box is not blown if equipped.
If it registers an excessive charge 15 volts or more the regulator is faulty and you should replace it.
What Causes A Faulty Alternator. The alternator makes sure to keep the battery of the car charged and power your vehicle. Still using a few simple tests at home that show you how to test an alternator how to inspect a battery if necessary and check a drive belt will help you pinpoint the cause of the problem. How to check your alternator.
