What is the red knob underneath the rearview mirror on BMWs?

Question

It is sort of see through, red in color, and not really that small, roughly the size of a thimble.

I have no idea what it does. It might only be on newer BMWs because the one I am driving is a 2007 330i, but I've seen it in the X5 SUV also

Answer 1

does it sorta look like a siren?? if it does, then it's the alarm indicator light. it will flash when you lock your car and engage the alarm. if you hit the lock button twice, the light will illuminate for a brief second, and then continue flashing. this tells you that your motion sensor has been disengaged. i almost always push the lock button twice on my BMW, that way something doesn't accidentally set off the alarm..especially if the windows are open, as the motion sensor will sensor anything outside the car. i only use the motion sensor when i am anywhere where i want my car to be as safe as possible, a.k.a. cities and 'bad' neighborhoods.

Answer 2

It is the visual indicator for the alarm. BMW "insiders" refer to it affectionately as the clown nose. Now, here's another piece of insider info....you don't have to pay BMW to install the OEM alarm in order to get the clown nose to blink. You can essentially have a blinking clown nose without having the alarm installed on the car. Kinda like having an ADT sticker on your house but no alarm. It acts like a deterrent.

Answer 3

Alarm indicator, also known as the "clown nose." If you don't have an alarm, it also can be turned to dim the rearview mirror.

Answer 4

It is the visual signal that your car alarm is set. It should blink after you lock the doors confirming that the alarm is set..

Answer 5

i think its the alarm sensor..they blink when the alarm is engaged

Answer 6

Press it..it could be an ejector seat...lol