26/05/2026
Modern SUVs, bakkies, and sedans in South Africa are built around a factory electrical system designed for standard driving loads such as engine management, lights, infotainment, air conditioning, wipers, and charging ports.
In average use, phone chargers, dash cams, and tracking devices are not high-draw accessories and have minimal impact on the electrical system. They only become relevant when there is a wiring fault, when they are installed on a constant live feed, or when the vehicle is left parked for extended periods with multiple small parasitic loads active.
High-draw accessories are aftermarket additions that increase electrical demand beyond factory levels.
The most common high-draw accessories in passenger vehicles are aftermarket audio systems and upgraded lighting.
Audio amplifiers and subwoofers place the highest demand. They draw sharp current spikes during use, especially at higher volume levels and in stop-start traffic where alternator output is lower.
LED light bars and auxiliary spotlights also increase load when used together. A single LED unit is efficient, but multiple units operating at the same time increase total current demand on the system.
The alternator charges the battery while the engine runs, but output varies with engine speed and electrical load. Short trips and traffic reduce charging time.
When high-draw accessories operate under these conditions, the battery supplies the shortfall. Repeated cycling reduces battery reserve capacity and leads to slower starting and reduced reliability over time.
High-draw accessories require correct installation. Direct battery connections, correct fusing, and properly rated wiring are essential to avoid voltage drop and battery drain.
Electrical issues in everyday vehicles are usually caused by combined load and driving patterns rather than a single fault. The system is designed for factory load, and added accessories change that balance.
Pop into your nearest branch of Battery Corp for a free battery test to determine whether the issue lies with the battery’s condition or electrical demand within the vehicle system.