Diagnosing electrical problems can be a real bear, because the first thing a malfunctioning system part is likely to do is to drain the battery. That means a lot of issues can mask themselves as a problem with that part. At the same time, powering up the vehicle and taking it to be tested at a place that can check the alternator, starter, and voltage regulator can be risky if the battery is failing. Before you head out to get help with your diagnosis, check the battery at home to be sure you don’t need to just place a quick order for a new one.
How Can I Test My Battery At Home?
Testing your battery at home with a multimeter is simple. Just hook it up to the battery and then have someone switch on the headlights. Don’t start the engine, though. You’re looking to get a reading on the battery’s power output on its own, without the alternator generating any current to recharge it. If the battery is fully charged, you should see a reading between 12.5 and 12.66 volts, depending on the temperature. If you see a reading between 12.3 and 12.5 volts, it represents a partially discharged battery. Charge it overnight to get it back to full, then try the test again to see if the battery was depleted or if it is beginning to fail. If it is still giving you a reading below 12.5 volts after being charged, it’s a good idea to replace that battery soon.
You can also perform a load test without any equipment if you need to know whether the electrical problem you’re chasing is the battery. The results will be imprecise, so it is a good idea to follow up with an AutoZone battery test to confirm your findings. First, turn the headlights on for approximately 15 minutes without starting the vehicle. After the time is up, attempt to start the engine. The headlights should dim slightly and then return to normal after the engine is running. If the engine cranks slowly or fails to start, the battery probably needs to be replaced because it doesn’t have the capacity to start under adverse conditions anymore.
How Long Does It Take To Test A New Battery
If you have a multimeter, a test only takes a minute or so apart from any time spent charging the battery. A no-equipment test takes a bit longer, but still only about 15 minutes. Regardless of the results, you may also want to schedule enough time to bring the car in to a place that lets you test the battery so you can confirm the reading. In most cases, this is just a multimeter test, but it does give you confirmation from a second piece of machinery. To save time, consider doing your battery check alongside other simple maintenance tasks like changing wiper blades. If you’re wondering what size windshield wipers do I need, you can get fast answers online with a simple search of your vehicle model and year. That lets you place your parts order with confidence.