Steps to Check Your Car’s Alternator
Step 1: Find the alternator.
Alternators tend to be located by the engine.
Step 2: Check the connections, fastening equipment, and serpentine belt.
If any connections are found stripped or worn, they should be replaced. If the alternator itself is loose, it should be fastened correctly to prevent it from losing proper grounding. The same can be said for the serpentine belt.
Step 3: Keep the alternator clean.
Since the alternator produces electricity, it’s very important to make sure they are kept cool. The less it needs to work, the lower the chances of it overheating. Any gunk or dirt over its shell needs to be cleaned to make sure it does not keep heat trapped.
Step 4: Prepare a voltmeter.
To check if the alternator is working properly, you can purchase an inexpensive tool called a voltmeter, which can help you test the battery as well. Set the meter to the correct dial (DC is usually what you’ll set it to and anything higher than 15 volts), then place the probes over the battery connections (red on the plus, black on the minus).
Step 5: Test your alternator
With the car off, it should read between 12.5 to 12.8. If it’s below that, your battery may be weak and need a proper charge to continue. Start the engine and make sure it reads between 13.8 to 15.3 volts with all lights, radio, or additional equipment off. If it does, the alternator seems to be doing its job.
This is a rough test and is not perfect, but at least it’ll give you a very good idea of whether you have an issue that should be further looked into.
Many auto parts stores offer to test your alternator for free with more sophisticated equipment. If you’re not comfortable using the voltmeter method, you can take advantage of that if your local parts store offers this.