Hi All,

My '06 MCS has the convenience package which includes the automatic headlights feature. In general, I love the concept and typically leave the switch in the "auto" mode; however, I'd like to know more about how it determines when to turn the lights on as it seems to activate the lights when it's still very bright outside.

I know there are (at least) three light sensors on my dash: 1) the "nipple" in the middle of the flat section of the dash, kinda under the rearview mirror, 2) a sensor above the nav screen and 3) a sensor below the nav screen to the right of the control ****.

I thought that sensors 2 and 3 were for the dash and nav illumination, leaving sensor 1 for the auto headlights and/or the climate control. If so, though, there are many times where that sensor is under full sunlight yet the auto headlights are on.

Typically when I'm on my way home from work, I periodically check the status of the amber ambiance LEDs near the sunroof control to see if the headlights are on or off and most times, even when I'm driving in full sunlight yet toward the end of the day, the lights are on.

Does anyone know more about which sensor or perhaps combination of sensors controls the auto headlights and anything more about the illumination thresholds for when the lights should be on or off?

Thanks for helping this geek out

 

I re-typed this info from a pdf file I downloaded from minitechinfo.com
(get 24 hours access for $25 - well worth the price if you save the pdf's to your hard drive - this site is BMW's site for access to dealer mechanic service bulletins, training docs, elec schematics and so on.... I hate the interface for the schematics, if you log into this system, make sure you download the adobe browser plug-in to support the vector graphic schematic interface they use....

Good Luck --------------------------------------------------------------

The new RLS (rain/driving-light sensor) replaces the familiar rain sensor already in use. The RLS now has the added functions of monitoring ambient light conditions to influence the operation of the headlights.

The driving lights (headlights) are turned on and off automatically based on input from the RLS depending upon ambient light conditions.

The new RLS contains two additional optical sensors integrated in the sensor housing. The RLS continues to use similar rain sensing electronics as used on the previous AIC system. The two additional light sensors are used for headlight operation.

The two sensors have the following function:

- Sensor number 1 is a surrounding-light sensor that records the light intensity in a wide angle above the vehicle.

- Sensor number 2 is a frontal=light sensor that records the light intensity in a narrow angle in front of the vehicle. A processor measures and determines which sensor is switched on.
The following conditions are monitored by the RLS:

- Dawn/dusk

- Darkness

- Driving through a tunnel

- Precipitation such as rain or snow.

If the wiper switch condition is on, the RLS transmits the information thru the K-bus to the central light switch (LSZ)

If the RLS switch position ("A") on the LSZ has been selected, the exterior and instrument lights are activated by the LSZ under the following conditions:

- One of the above RLS conditions is satisfied.

- The front fog lights are switched on.

NOTE: If the front fog lights are switched on and one of the above mentioned RLS conditions are satisfied, the exterior lights will only go out after the front fog lights have been turned off.

In addition, the lights are switched on in the event of the following malfunctions:

- The RLS has detected a sensor fault.

- Communication between the RLS and the LSZ is disturbed.

The following lights are switched on by the LSZ:

- Terminial R turns on the parking light, the low beam headlights, the license plate light and instrument lights.

- Terminial 15 turns on the parking light, the low beam headlights, and the license plate light. In order to switch the parking light on, the LSZ switch must be set to parking light position on.

- With the ignition switch in the "O" position, the exterior and instrument lights are switched off.

The sensitivity of the RLS can be adjusted by means of the car memory function.

NOTE: During bad weather and fog the driver must switch on the fog lights manually. The automatic driving-light control will not turn the fog lights on during bad weather conditions.

 

It might not be clear from MadHatter's very informative note, but the rain/headlight sensor is on the windshield in front of the rear view mirror. There have been numerous complaints that the automatic lights turn on when it is bright outside. There is a new dealer programmable option in 2006 where they can set it to less/more sensitive (this is listed in the owner's manual).

 

Hmmm.... and my dealer told me specifically there was NOTHING that can be done for the overly-sensitive auto headlights. Guess NAM has more knowledgeable tech resources then the dealership... I will have to find the page in the owner's manual that mentions that, and kindly point that out to them.

Thanks for the heads-up on that info...
.

 

Thanks for the informative answers! I now feel a tad more knowledgeable on the whole issue. So, just for clarification, is the sensor on the dash (the nipple-like one) used only as a sunlight sensor for the auto climate control and all headlight sensing is done via the wiper sensor behind the rear view mirror?

 

It is the sensor behind the rear view mirror. Auto-headlight and auto-wipers are together as a single option ordered from MINI, and this would be consistent.

Here is the note in my 2006 Owner's Manual (on page 59 under Automatic Headlamp Control): "You can have the sensitivity of your vehicle's automatic headlamp control adjusted". The icon next to it indicates dealer settable options.

 

it is inside of the rear view mirror... behind the mirror implies being somewhere else... I had to think about this for a while...