Automotive Battery and Electrical System Testers

Automotive Battery and Electrical System Testers

Modern charging system testers are programmed to know what they should see on each and every vehicle.

Ohm’s Law never changes. It’s the mathematical relationship between voltage, amperage and resistance. It can’t change. It’s science. So, if that’s the case, does your electronic equipment need to change? Conventional wisdom might want you to say no, but technology says yes.

I used to be as guilty as anyone. I had test lights and I had an analog voltmeter. What else did I need? Not to mention the shop had a Sun VAT-40 and a Sun Engine Performance Tester. I came into the industry when all these now-dinosaurs were gasping their last breaths of usefulness in the industry. But I wanted to resist change. I needed to buy a multi-what, you say?

Resisting change is just a natural reaction that affects a lot of us, but after a while I realized that I was only going to be successful by embracing new technology – and buying the tools I needed to work on it. Now, with more time to focus on new tools and equipment, I’m envious of how advanced, compact and affordable it has become. I wish I had today’s tools many years ago.

Affordability always was and is a concern, and that’s not to confuse affordable with poor quality. Years ago, there was definitely truth to that — inexpensive tools were cheap and poorly made. It took a long time to close the gap between quality electronic equipment and affordable price, but technology made it happen.

The same technology leads the way in every aspect of the automotive industry, and when it comes to repair, our equipment must step up to the plate. If we stick with the old that we’ve had for years, we are shortchanging ourselves and our customers. The bottom line is old electronics just don’t cut the mustard.

Let’s look at automotive batteries. There was a time when I had these mastered. All I needed was my battery hydrometer and a traditional load tester. I could tell you everything you wanted to know about that battery. But then they started to change the batteries. First there was maintenance free. Then there was sealed, and we couldn’t even pry the caps off and “cheat” if we wanted to add water. Now there are absorbent glass mat and gel cell batteries in the mix.

You know what the old equipment doesn’t do? You’re right. It doesn’t cut the mustard. I love digital battery testers, but I didn’t trust them until I understood how they worked. After all, a hydrometer was easy to understand. It measured the specific gravity of the electrolyte in each cell of the battery, telling you the state of charge. It was a real, physical, live test.

So, the digital testers? They work by measuring battery conductance, which is ultimately a determination of the available plate surface inside a battery. As a battery is used over time, two things happen that are part of the normal wearing process. One, the plates become sulfated, meaning they have a buildup of lead sulfate crystals on the plates. Sulfation is normal to a certain degree, but overcharging, storing with a low charge and storing at high temperatures can accelerate the process. Two, the active material on the plates sheds off as part of the normal chemical discharge and charging process.

When either of these occurs, the available plate surface inside the battery is reduced, and a digital battery tester takes into account the original battery rating, temperature, voltage and conductance to determine the overall condition. I’ve been using them for years with an interest in their accuracy, and I have no basis for any claim that they are anything but.

The reason digital battery testers are so important is they are quick and easy, and they are accurate even on a battery that is not fully charged. A weak battery can cause a lot of problems on a modern vehicle with multiple electronic control units. It’s important to identify battery trouble long before a vehicle won’t start or begins to set low voltage trouble codes.

Every time a car is in the bay, a digital battery tester makes it easy to check the battery. Not only is it important to your customer, but it’s a good upsell for you. If you don’t catch it, someone else will. Don’t let battery sales walk out the door.

I know what I said about the mustard, and it may get a little dusty back in the corner, but don’t let that traditional battery load tester go, and if you don’t have one, it’s still an incredibly valuable piece of equipment. While I never doubt the results of my digital battery tester, if there’s a starting or charging concern and it indicates anything less than a perfect battery, you have to remember that these tools are assessing based on logic, and we know sometimes in this field you can throw logic out the window. If there’s any question about battery condition, a traditional load tester will give you absolute results. A weak battery has no way to hide from a load tester.

Digital battery testers are available as simple, stand-alone units, but with the advanced technology we are able to put in tools, why stop there? Nowadays, people like printouts. They are proof of the battery test results you can share with a customer. Dealer equipment has featured built-in printers for many years. Now it’s available on the equipment we put in our toolbox. That “transparency” — the trend in business to be able to demonstrate that you are open and honest with your customers — is a continuously growing aspect of our business, and one that’s valuable to embrace.

I like the printers. Now I don’t have to write down the results, try to remember them or try to read my own writing an hour later. The equipment does it for me, and to a greater degree of accuracy.

But it just keeps getting better. Now, there are many more features incorporated into battery testers. How about something that is a complete electrical system tester? Starting and charging system testing is now a quick and easy process, and modern testers are programmed to know what they should see on each and every vehicle. They utilize VIN scan technology or automatic identification to save you time. If there are specific procedures for certain tests, you can eliminate the guesswork. Modern testers walk you right through it.

Here’s another challenge technology has thrown at us: computer-controlled charging systems. Gone are the days when charging system output was a fixed range you could count on for every vehicle. Modern charging systems monitor battery state of charge and take into account electrical load in order to provide the most accurate and fuel-efficient operation of the charging system. Try checking the operation of these systems with old equipment. It won’t happen. You’ll need to add a scan tool to your list. Since these smart systems monitor battery condition and state of charge, when you replace a battery, you need to register the battery information with the vehicle, so when it performs a conductance test of its own, it can properly analyze the results. Without it, proper control accuracy of the charging system is not possible.

Since vehicle identification is important for any new electronic equipment to know the specific functions it can have, it almost goes without saying that OBDII communications are built into many new testers, and they have also advanced to include basic code reading functions and, in some cases, live data as well.

Could there possibly be icing on the cake? Throw in Bluetooth connectivity to the OBDII dongle and Wi-Fi connection so you can send detailed data reports to share with your customer, once again hitting that important element of transparency These new tool and equipment manufacturers are sure on the ball, making our jobs easier, aren’t they?

 While you’re doing battery and charging system tests, why not add a multimeter to the list of functions you can find on a modern battery tester? There’s no reason not to. It’s been done. It’s amazing how we have been able to pack so many great functions into a piece of handheld equipment.

If you want something that gives you the functionality for modern systems and more, take a look and see what’s out there.

I think you’ll agree. It’s time to update your electrical testing technology. You’re sure to find something that’s a condiment to your toolbox.

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