How to Troubleshoot an Alternator on a Dodgeby Arthur Barnhouse
The alternator on your Dodge, whether it's a car, truck or van, is an essential piece of its electrical system. In fact, if the alternator is not working perfectly, your Dodge will soon begin to experience serious problems. For example, with an improperly functioning alternator, the battery will quickly drain. Without a fully charged battery, the vehicle will not start. Thus, with a bad alternator, you face the risk of being stranded anywhere at any time. Thankfully, there are things you can do to troubleshoot your Dodge's alternator in your own garage.
Open the hood of your Dodge with the engine turned off. Also check to make certain that all other switches and/or electrical components have been turned off.
Locate the alternator. Depending on your model of Dodge, the location will vary. It will, though, have a belt running to it. Check this belt to make sure it is tight. If the belt is loose, you can try tightening it by adjusting the alternator on its mounting bracket. You will need a wrench or socket set to accomplish this. Also, while you have your tools and with the engine still turned off, you should remove any guards or covers from the battery.
Connect the digital voltmeter to your Dodge's battery terminals. Be sure to connect the positive clip on the 12-volt voltmeter to the positive post and the negative clip to your battery's negative post. The reading you receive will reflect the charge of the battery alone. A reading around 12.5 or 12.8 volts is normal. A reading below 12 volts may indicate your Dodge's battery is the culprit. Charge the battery and, without running the car in the meantime, test it again the next day. Another low reading would mean that your battery is bad or that you have a short circuit in the wiring.
Disconnect the voltmeter from the battery posts and ask a friend or family member to get behind the wheel and start the Dodge. Then reconnect the voltmeter to the battery exactly as you did before. Now ask your friend or family member to turn on the Dodge's headlights and trip them to high beam.
Look at the voltmeter. At this point, you should witness a reading anywhere from 13.8 to 14.2 volts. A variance of a few tenths of a volt is okay. Now ask your friend or family member to increase the RPM of the Dodge to approximately 1,500 or a fast idle. Read the voltmeter again. This time a reading between 14.2 and 14.6 volts is the norm. If you see anything below 14.2, your Dodge's alternator is not providing enough voltage to keep the battery fully charged.
Listen to the Dodge's alternator while the engine is running. The alternator should be quiet. If you hear squealing, rattling or grinding coming from the alternator, it will need repair or replacement.