Why do car batteries need to be managed with diagnostic tools?

June 29, 2023
Although battery management has been around for well over 100 years, since the 1912 Cadillac, it has transformed with the times with different technologies. Keith Wray from Snap-on Diagnostics takes a closer look by using a scan tool on a Land Rover.

Before we dive into diagnostic battery management, I’m going to start with a miniature history lesson to show you how the electric starter came on the scene resulting in the need for today’s modern automotive battery.

Later, we’ll use a TRITON-D10 diagnostic tool in our Land Rover case study.

History of car batteries

Over 100 years ago, cars did not have batteries. A bell or a bulb horn was used instead of an electric horn and carbide headlamps were standard, while the engine was started with a crank.

Carbide lamps are powered by the reaction of calcium carbide with water. This reaction produces acetylene gas which burns a clean, bright, white flame. Back in those days, miners would use a hat with a carbide lamp mounted to it to act as a headlamp.

Let’s get back to the hand crank start for a minute. I have never used one, but I have used a kick starter on a motorcycle resulting in a pronounced limp for a few days. I can only imagine a backfire during a hand crank.

Back then, there was more to it than simply turning the crank. After connecting the handle to the crankshaft through a hole in the grill, one would prime the engine. Next, they’d adjust the throttle and ignition timing. A misstep anywhere in this process could result in a backfire, which would violently drive the crank handle in the opposite direction you were cranking. That’s the reason most people would not wrap their thumb around the handle and would use their left arm to crank – just in case an incident like described above would occur.

Old-fashioned car horn (left) and a vintage carbide headlamp (right)

As the story goes, in 1910 a man named Bryon Carter stopped to help a woman whose Cadillac had stalled on a bridge in Detroit, Michigan. The engine backfired and spun the iron crank into his jaw, causing it to break. His jaw got infected, and he unfortunately passed away due to the injury. Henry Leland was a close friend of the tragically deceased Carter. Leland just happened to be running the Cadillac division at that time and he was quoted as saying, “The Cadillac car will kill no more men if we can help it.”

Meanwhile, an inventor by the name Charles Kettering had been working on several automotive innovations. An electric starter motor had been patented but was not yet feasible for mass production for an automobile. Leland tasked Kettering with designing something that would work. Kettering soon patented his own design, and with his business partner, founded a new company to handle the work of producing these starters. It was named Dayton Engineering Laboratories Company, or Delco.

The new Delco starter motor was installed on a 1912 Cadillac Model 30. It also featured some of the first electric headlights in the industry. The marketing folks at Cadillac simply dubbed it, “the car that has no crank,” which instantly doubled sales.

By 1920, car batteries along with electric starter motors, became standard equipment.

SLI batteries come onto the scene

The first car batteries from that time period were 6V lead acid. Named after their main functions, the SLI battery stood for starting, lighting and ignition.

My old 1951 Chevrolet pickup had a 6V system. I drove it for a year with a bad battery because I could not afford one at the time. It was easy to park on a hill – let it roll and pop the clutch to start. Or a buddy could ease his truck up to mine and touch bumpers, that was a ground connection. Another trick to get the car going was using a piece of barbed wire – you could connect the two positive post on the batteries and my Chevy was up and running. When I finally saved enough for a battery, I learned that an eight-volt battery was available for a little more oomph. That’s exactly what I bought, and it performed as advertised. Please do not attempt to any of my old “fixes” as they are not recommended in this day and age.

In 1953, GM switched to 12V systems in the Cadillac, Buick, and Oldsmobile models. Chrysler also followed suit in 1956.

In 1956, Ford, Lincoln, and Mercury all came out with the new 12V systems.

Smaller automobiles, like the VW Beetle, opted to stay with the 6V systems until the mid-60s. By then, the majority of the automotive world was run on 12V.

Other than the maintenance free battery coming out in the ‘70s with the Delco Remy Freedom battery, and the AGM battery, not a lot has changed, really.

In fact, if you really think about it, battery management has been around in some form for well over 100 years, since the 1912 Cadillac. It used a starter/generator that had a charge controller that would manage the amount of charge with resistance or through a cut-out relay.

Since then, battery management has been the norm, but has transformed with the times with different technologies.

Of course, with the current computer technology, battery management has taken on an entirely different path, but with the same objectives. Trouble free and longevity, right? This is where diagnostic scan tools, like our OBD car scanners shine.

Let’s focus on Land Rover battery management and see how this advanced technology makes working with a diagnostic car tool a breeze in this case study below.

Case study – Land Rover battery management

  1. 2016 Land Rover Range Rover Sport 5.0L V8 Supercharged
  2. System Diagnosis determined that the vehicle’s battery is non-functional
  3. Replace battery
  4. New battery is out of calibration with the vehicle
  5. Using Service Resets & Relearns to replace and recalibrate the vehicle battery, the charging system can ensure that delicate electronic modules are not subject to overcharging. With the new battery calibrated to the vehicle, it can operate at peak efficiency and prevent potential damage to critical electronic components.
  6. Perform test drive and confirm repair

Once the battery has been replaced, prior to starting the vehicle, the battery needs to be recalibrated to the vehicle. Using Service Resets & Relearns, the battery is properly calibrated to the vehicle. This process synchronizes the charging system with the new battery to prevent overcharging, which can cause damage to sensitive modules in the vehicle.

We used a Guided Component Test to access the Battery Monitoring System (BMS) module to verify all is well with it and the charging components.

So, that’s the story of battery management spanning the last 110 years.

Information provided by Snap-on Diagnostics 

About the Author

Keith Wray

With over 45 years of experience in the automotive industry, Keith Wray started his career as a technician/automotive machinist and worked his way up to a service manager for an OEM dealership. He currently serves as the national training manager for Snap-on Diagnostics where he co-develops training materials as well as conducts technical courses for franchisees, employees, end-users, and vocational students.

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