How to Reset the Service Engine Light in a BMW 3 Series

1. Put the key in the ignition and turn it on, but don't start the car.
2. Shut off the radio, lights and air conditioner fan.
3. Lift up the hood of the car and plug the reset tool into the diagnostic connector. This is located on the left side of the engine toward the front, if you are standing in front of the car looking at the back of the car.
4. Push and hold the 'Service Engine' button on the reset tool. In about 10 seconds a light will flash then go out. When it goes out, let go of the button.
5. Look on the instrument panel to verify that the service engine light has gone off.