By YOUCANIC on Jan 29, 2019
Newer BMWs are now equipped with Auto Start Stop function. The main purpose of auto Start/Stop is to save fuel.
Every time you stop at a red light or are stopped in traffic the engine turns off. Everything in the car including the ignition remains on. As soon as you take your foot off the brake the engine starts again automatically. It takes about 1 second for the BMW engine to restart.
BMW auto Start/Stop can be turned off. BMW will remember the state of Auto Start function even if you turn off the engine and park the car. In other words, when you enter the car again, your BMW knows if you had the Auto Start on.
Several conditions need to be met for the engine to automatically stop and restart.
Here are the primary requirements.
If these conditions are not met you will notice a cross on the Start/Stop symbol on your instrument cluster.
Under certain conditions, BMW may not restart, for example, if the engine is turned off during auto shutoff, you open a door or remove a seat belt. If this happens to you, try restarting the car by pressing the Start/Stop button.
BMW auto stop does not work on reverse gear.
BMW auto start function does not work if you are driving at speeds less than 5 mph or about 8 km/hr. Your BMW instrument cluster may display a symbol stating READY which means the car is ready to start the engine automatically.
Your BMW auto engine start may not work in several situations. List of cases under which engine stop/start feature will not work.
In some cases, you may notice that the engine restarts, even though you haven’t started to drive yet. There are several conditions that can trigger BMW engine to restart automatically.
If you experience problems with the Auto Start/Stop feature, you will need to read the fault codes from the control module. This can be done with a scanner that is capable of reading BMW specific fault codes. A generic OBD2 scanner cannot read fault codes or troubleshoot Start/Stop function.
For more information follow this article: How to read BMW fault codes