My buddy drives an 01 E46 and he told me his SES was on. I checked it out and it's on with his key in the ignition in the "on" position and will not turn off. Once he starts the car, the light turns off. I didn't notice rough idle or rough engine while driving.
Is it normal for that light to stay on? In my experience; it would come on and then shut off after a few seconds... but I'm unsure.
thanks in advance!