Why doesn’t start stop make the radio, lights etc cut out?


When I start my car from fully off, (and have driven other cars with start stop and they also behave the same) whether it be after it’s been turned off for several hours or if it’s seconds or minutes after turning it off, the radio, lights and other auxiliaries will cut out until the engine is started, which I understand is a feature as the starter motor requires a lot of energy. However, when restarting from start stop, this doesn’t happen, everything stays powered on. I believe that with start stop, the fluids continue circulating, but I would have thought the starter motor would still need a lot of energy to start the engine, so what exactly is different between the 2 starting systems that means 1 can keep power to auxiliary components and one that cuts everything off?

In: 4

It’s basically just a highly optimized. I think the biggest change is that start stop engines usually have two solenoids (basically contacts that transmit power from the battery to the starter motor). When you start the ignition the starter motor needs power from the battery to start spinning, and then that causes a rod with a gear on it to extend and spin, meet up with a gear on the engine, and causes that to start spinning which moves air through and starts the engine. With a start stop motor one solenoid starts the motor spinning and a second causes the rod with the gear to extend, which actually requires much much less electricity.

Some other stuff, by better optimizing gear ratios the starter can spin at a slower speed to start the engine and use less electricity. They also are usually optimized so that when you stop the cylinders are in optimal position to start firing right away – with a traditional starter you have to wait for the cylinders to start moving and cycle through until the first is ready to start injecting fuel and sparking.