(Something that requires a fresh set of AAs is going to fail when you need it to work most.) This thing is going to be hanging in your garage - unused - for years. It doesn’t require batteries to operate.You can usually buy one for less than $40.There are fancier electronic testers, but this old-school analog tester has a couple of advantages: CEN-TECH 100A 6/12v Battery Load Tester/Image Credit: Harbor Freight This kind of tester not only tests the state of charge at rest but also the health of the battery while it’s subjected to the load of a start cycle. The first thing to consider purchasing is a battery tester with a load tester. You’re going to need a few diagnostic tools, but we’ll keep it to the absolute minimum. We’re not only going to describe how to test these components but the order in which you should be testing, which will uncover typical problem areas and save you from spending more than you have to. You don’t want to spend that money unless the battery truly is the problem.

These days, you’re looking at $140 to $200. There was a time when $75 would buy the best battery on the shelf. But it’s not the only component that needs to be inspected and replaced, and as the years have gone by, it’s become one of the more expensive components in the charging system. The battery is a vulnerable component because it can be weakened by age, temperature, and even vibration. This diagram is a little basic and out of date, but it roughly explains the components of a typical 12-volt charging system: Automotive starting system/Image Credit: ResearchGate If the battery terminals are clean and properly connected, and a battery tester shows that it’s in good shape, you’ll need to keep troubleshooting to find the problem. The vast majority of the time when a vehicle refuses to start up, the cause is a battery with little or no juice. When your car won’t start, the first thing to do is check the battery. Car battery being tested/Image Credit: mikrob111 on Pixabay

Battery charger needle not moving