Autoelectro UK’s Sales Manager Nick Hood outlines the evolving partnership between battery, starter motor and alternator.
The relationship between the vehicle battery, starter motor and alternator is a longstanding one that is generally understood. However, if the last decade is anything to go by, with the advancing electrical systems, driver aids and functions seen in modern cars, such as start-stop, this relationship is as crucial as ever. All three parts have been part of an era of significant technological advancement to improve their use and performance, to accommodate new demands on the modern vehicle.
As the winter season approaches, a time when the demands placed on the components increase, this season could see more vehicles back out on the road after a period of infrequent use, which, in many instances, could lead to poor or low battery condition.
A deteriorating battery has implications for the starter motor and alternator, which can be worsened by the arrival of cold weather. A frosty morning, coupled with low battery condition, can cause prolonged cranking to start the vehicle, something that a modern geared starter motor is not built for and can easily result in the starter motor burning out.
Switching to the alternator, it is wise to remember its proper function: maintaining battery condition, whilst running the vehicle’s electronic systems; it is not designed to charge a flat battery, and it can struggle to recover a partcharged battery.
Both of these scenarios can result in the alternator being in constant use and demand – something it will struggle to cope with. If an alternator is working beyond its capacity, it will, inevitably, get hot and the heat generated can blow the regulator and/or rectifier. As the winter season looms, therefore, technicians should ensure they’re passing on best practice tips to their customers, which will not only protect the vehicle’s battery, but will avoid starter motor and alternator issues as well.