Red bulb on rear view mirror

[EnvyM3]

There is a large red bulb hanging from the rear view mirror in my 2000, 323ci and I got no clue as to what it is for. My guess would be the alarm but there is no alarm on the car?

[mankiks323i]

: yes for alarm most 3 series i have seen have them with or without alarms

[2001BMW325xi]

I though that was the infra red sensor that makes the interior light s come on while unlocking the car only when the outside lights are less (night and cloudy) and not in the day time????? ghead maybe I am wrong but I have one too ........

[KennyH]

Yep, for the alarm. All vehicles fitted with the light, even if the alarm option itself is not installed. BTW, if you ask, your BMW service department can set your preferences so that the light flashes when you exit the vehicle, even if you don't have an alarm. I guess that's a small deterrent for the casual theif.

[2004_325Ci]

It should also adjust your rearview from "day" to "night" mode (to reduce headlight glare at night). Just twist it and the mirror adjusts.

[2001BMW325xi]

Actually the 2001 BMW 325xi I have has small photocells inside the rearview mirror that autodims the mirrors according to the light falling on it.....you dont ahve to adjust the mirror.

[gordo325xiwagon]

It is called the 'clown nose' ....