top of page

Chain Reaction


Sometimes you don’t know what you don’t know. Dismissing recommended maintenance can backfire in the long run.

You just had your vehicle in for service. Your mechanic recommended replacing your battery as it failed the battery test performed with a professional battery test tool. Your mechanic may even have recommended replacing your battery based on the battery’s age.

Is this just your mechanic hungry for extra money from your pocket? Your vehicle has started every day and you have experienced no battery problems as far as you’re concerned. Why not just wait until you recognize a battery problem?

Many customers are quite proud when they return for their next service still sporting the same battery under the hood. The battery fails testing again yet the customer says “You said I needed a battery last time and I haven’t had a problem yet. I’ll roll the dice. My luck is good.” “What can go wrong?”

Your vehicle battery is part of a system of several components. It is the backbone of the vehicle’s electrical system. Along with providing the electrical power to start your car and run all the ancillary devices the battery is a cushion of sorts. It is there to absorb voltage spikes and provide a stable voltage to the electrical system.

As a battery begins to fail it takes its toll on your vehicle’s total electrical system. The starter is one component that suffers when exposed to a failing battery. A weak battery presents a lower voltage to the starter. When your engine cranks over to start battery voltage drops. The lower the voltage the higher the current draw through the starter. At higher current the starter experiences higher temperature and more severe internal sparking and component wear.

While you continue to be pleased with saving your money by not replacing that old battery your starter is more quickly wearing out.

Another component that suffers with a weak battery is your alternator. The alternator is not a battery charger. It was designed to maintain the battery while providing the necessary power to run the vehicle. Many failing batteries require a constant flow of current into them to keep them charged. In doing so they present a constant extra load on the alternator. That extra load means a harder working alternator producing more current.

Again as you are driving around with that smug look on your face happy with the extra money you have saved by not replacing your battery your alternator is working double duty. Believe me premature replacement of that alternator will be a more expensive job than a simple battery.

Modern vehicles are basically computer networks. Computer networks need clean steady power. Failing batteries do a poor job of keeping a steady system voltage and absorbing system spikes. Voltage spikes hurt electronics.

We all know how expensive automotive computer modules can be. A poor battery will do a poor job of protecting these modules. Premature failure can be the result of a poor battery.

So you got an extra year or two out of your battery. The chain reaction of failures later on in vehicle ownership may be the result of that extra time driving with a failing battery.

Fortunately or unfortunately you likely will not recognize that you needed a new alternator, or starter, or computer module because you got a couple extra years with a bad battery.

bottom of page