Are you having electrical problems with your car? Maybe an illuminated warning light on your dashboard is telling you to check all things electrical, and when this happens, you may automatically think about the battery. Remember, however, that the alternator is the most important part of any vehicle's electrical system, and this energy generator comes under considerable pressure in a complex, modern car. Is the alternator at fault now or is the system simply overloaded?
How the System Works
To boil things down to basics, the battery is essentially a storage device that will feed a large number of electrical components when the engine is running, while the alternator keeps this device fully charged. In order to run all electrical accessories on any vehicle, the alternator has to work very hard generating an alternating current that feeds the battery.
Accessories Galore
Problems can arise in the modern-day car due to the number of accessories and the amount of 'draw' that they place on the charging system. For example, you may be driving down the road with your headlights on, windshield wipers in action, air conditioning system on max and a rear window defogger at work. You may also have your stereo system playing on full blast and your cellphone charger switched on. When you take all of this into account, you may be requesting more from the alternator than it can adequately deliver.
Overload and High Heat
Don't be surprised if your warning light comes on in this type of situation, even though there's nothing wrong with the alternator itself. After all, much will depend on the electrical load, especially when the engine is idling at a traffic light. The situation is compounded on a typically warm Australian day, as high heat conditions can lower the alternator output even more, affecting the electrical resistance and reducing its charging capacity.
Stop/Start Technology
Don't forget that many modern cars are fitted with an automatic cut-off whenever the vehicle is stopped for more than a few seconds, and this can play its part as well. The engine will need to start up more often, using valuable energy, and some systems delay any battery charging for several seconds while this activity is taking place. Once again, this can affect alternator output and may trigger that warning light on the dashboard.
No Need to Worry?
So, you don't necessarily need to panic if that light comes on but may simply be experiencing excess load. However, if you're not sure and don't want to risk a breakdown, take the vehicle into a mechanic for auto servicing.