S/S in cars stands for Stop/Start System, an automated feature designed to improve fuel efficiency and reduce emissions. When you come to a complete stop (like at a traffic light), the system automatically shuts off the engine. The moment you lift your foot off the brake pedal, it restarts instantly. The primary goal is to conserve fuel that would otherwise be wasted while idling.
The system uses a network of sensors to monitor the battery's charge, engine temperature, and cabin climate. If the battery charge is insufficient or the cabin hasn't reached the desired temperature, the system may not activate to preserve resources. You'll typically find a dashboard button marked "A" or "S/S" that allows you to temporarily disable the feature if desired.
The benefits are clear: reduced fuel consumption and lower tailpipe emissions, especially in city driving with frequent stops. However, some drivers find the engine restart jarring or express concerns about potential wear on the starter motor and battery. To address this, automakers use heavy-duty components designed for the increased number of ignition cycles.
| Vehicle Type | Typical Fuel Savings in City Traffic | Emission Reduction |
|---|
| Compact Sedan | 3-5% | 5-7% |
| Midsize SUV | 4-8% | 6-10% |
| Full-Size Truck | 5-10% | 7-12% |
| Hybrid Vehicle | 8-12% | 10-15% |
While the fuel savings might seem modest on a per-trip basis, they add up significantly over time and contribute to a cleaner environment. The technology is now standard on most new vehicles and is a key part of meeting global efficiency regulations.
