BMW Auto Start Stop Explained
Updated 8 months ago
Newer BMWs are 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 agian, your BMW knows if you had the Auto Start on.
1. How is Engine Auto Stop activated?
Several conditions need to be met for the engine to automatically stop and restart.
Here are the primary requirements.
- Transmission is in the Drive position.
- The brake pedal is pressed and remains pressed.
- Seat belt buckled
- Driver’s door is closed.
If these conditions are not met you will notice a cross on the Start/Stop symbol on your instrument cluster.
Note that 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.
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.Back to top
2. How to Disable BMW Auto Start StopBack to top
3. Why is my Auto Engine Start/Stop not working?
Your BMW auto engine start may not work in several situations. Here are some cases under which engine stop/start feature will not work.
- In extremely hot days
- In extremely cold days
- Interior temperature has not reached your desired level.
- Engine hasn’t warmed up to optimal temperature
- Wheels are turned all the way to the left or right
- Driving in reverse
- Car battery is not fully charged
- At very high elevation
- Hood is not propley locked
- Stop and go traffic
- Used wrong fuel octane or too much ethanol
4. BMW engine starts even though I haven’t started driving
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.
- The temperature inside your car has changed drastically from yoru desired temperature
- The car battery is beign discharged to quickly
- WIndows foggings
- If the BMW starts to roll with the engine off
- You move the gear shifter to Neutoral, Reverse or Park.
- You move the steerign wheel while the engien is off.
- Temperature isnde the car increases too much.
- You press the A off button above the Start/Stop.
5. Problems with BMW Auto Start/Stop
If you experince 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 code reader can not read fault codes or troubleshoot Start/Stop funciton. Read the following articles for more help: How to read BMW fault codes