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When good alternators seemingly go bad

What’s Up with My New Alternator that’s not Working

Here’s news that’s surprising to hear. Some alternators are needlessly replaced, and some good alternators are returned to the seller when they perform beautifully on a bench test. How could that be? Sometimes alternators appear to have failed when there are other problems in the charging system. Before you replace your alternator, or before you send a new alternator back for an exchange or refund, check out these issues first. Doing a complete charging system inspection can save you time and money.

Check for Worn Wires and Corroded Connections
Many electrical problems are the result of bad wires and connections. Frayed wires and corroded connectors may seem small, but they can cause big problems. You might start with a visual inspection of the wires and connectors, but that won’t always reveal all problems. Using a voltage meter may be needed to diagnose flaws in the system.

Look for Battery Cable Problems
A poor battery cable connection can cause failure that mimics a bad alternator. Check out all the cable connections to verify they are all clean and tightly fastened.

Inspect the Voltage Regulator
If the voltage regulator is not working as it should, it may deliver too much or too little power to the battery. Too much power can damage wires and the battery itself. Too little power can make it appear as if the alternator is not functioning well, even when it’s working at full capacity.

Test the Battery
When the battery becomes too weak, it won’t hold a charge even though the alternator is operating just fine. If the battery is old, you might consider replacing it along with the alternator. A fresh start for both the battery and alternator is often a wise investment. At the very least, recharge the battery to get it fully charged before starting the vehicle.

When you’re fixing a problem in the electrical charging system, you need to be a detective to uncover what’s going wrong. Just be sure to investigate all the potential suspects before you assign blame to any one. A thorough checkup will save you from ordering parts you don’t need or returning parts that work just fine.