The rain sensing wipers on my "06 S acted up this summer, where they would start acting just like the regular low speed setting, not slowing down or speeding up with changes in the amount of rain. The dealer, of course, could not find any problem. Now, when I activate the rain sensing function, they will swipe once or twice, but that's it. Any ideas? Thanks!

 

Ever have the windshield replaced ? Wonder if the sensor was damaged during install ?

 

Thanks, but no, the windshield is original.

 

Get the dealer to recalibrate the rain sensor on the windscreen.

from EWS

AUTOMATIC INTERVAL CONTROL (AIC)


AUTOMATIC INTERVAL CONTROL (AIC)

Function

With the aid of a rain sensor, the automatic interval control (AIC) system senses water or dirt on the windscreen and activates the windscreen wipers accordingly.
The AIC consists of an optical element bonded on the windscreen, to which an electronic evaluator is connected.
The system is active as of ignition lock position 1. The wiper/washer switch must be set to the first stage (intermittent wipe setting).
The wiper motor is activated by the general module of ZKE. The electronic evaluator sends the instruction to activate the wiper motor via the K-bus to the general module.

Optical element


The optical element is adhered to the windscreen behind the rear-view mirror. It consists of a glass body (prism) which routes the beams emitted by infrared diodes at a defined angle to the windscreen. The light beams reflected by the windscreen are routed by the optical element to the infrared receivers.
The optical element is heated by a heating element to ensure condensation cannot form on it.
The optical element is bonded together with the windscreen in a special process such as to guarantee the physical properties of the system. This bonding process cannot be carried out in the workshop. Therefore when replacing the windscreen, a special windscreen with the optical element already bonded to it must be used.
Electronic evaluator

The electronic evaluator is connected to the optical element by means of a catch mechanism.
It contains the electronic components as well as the infrared diodes and infrared receivers.
The instruction to activate the wiper motor is given via the K-bus interface.
Functional principle

Water on the windscreen is detected on the basis of the reflection of infrared beams.

When the windscreen is dry, all of the beams sent out by the infrared diodes ”S” that hit the windscreen with a defined angle are fully reflected by the windscreen and thus reach the infrared receiver ”E” in full.

A proportion of these beams is deflected by a drop of water on the windscreen (in the area of the infrared diodes). These beams no longer reach the infrared receiver ”E”.
Depending on the amount of light in the infrared beams that reach the receiver, the degree of wetness (or soiling) is determined and, if applicable, a command is sent across the K bus to the general module BC1 to activate the wiper motor.
Operation

To switch on the automatic interval control, the wiper/washer switch must be moved up to the first stage (intermittent wipe) and the ignition lock must be switched to position 1 or 2.
The automatic interval control system then controls the wipe intervals. If the windscreen is constantly wet (steady rain) the system activates continuous wiping in stage 1.
The wiper stage 2 can still only be set by way of the wiper switch (third stage).
Automatic interval control remains switched off if terminal R is switched off and on when the wiper switch is set to intermittent wipe. It is not activated before intermittent wipe mode is switched off and on.
Operating conditions

The following conditions are necessary to ensure trouble-free operation of the rain sensor:

• The windscreen must not be damaged (stone chips, scratches) or must not be heavily soiled (finger marks, streaks, wax film) in the area of the rain sensor.
• The wiper blades must wipe the windscreen dry without streaks.

To ensure trouble-free operation, the windscreen should be cleaned regularly with a suitable wax-removing cleaning agent. The wiper blades should be replaced regularly.
Initialisation

The reflection characteristics of the windscreen depend on a large number of factors. In addition these characteristics also change as the windscreen ages.
During the initial wipe cycles, a new electronic evaluator determines the degree of reflection of the windscreen and stores this data in its non-volatile memory. From this point on, this data is constantly adapted to the windscreen which is subject to a certain degree of ageing over the course of time.
The stored adaptation values can be deleted with the diagnostic program (service functions). Renewed adaptation (initialisation) to the windscreen can then be carried out.
The initialisation procedure is described in the program sequence.
Initialisation is necessary:

• After replacing the windscreen
• When a used electronic evaluator is installed in a vehicle

 

Chris, can you please not be so vague?

Just kidding. That is one detailed and informative answer. Posts like these are what make NAM great.

 

You are very welcome, I like to be concise..........

 

So after having my windshiled replaced my Auto wipers dont work. They swipe once like they used to letting you know they are on. But that is it. I saw he spray water on the sensor and they worked. Now today 2 days later in the rain they don't work. Any help?

 

Hey Braminator!

Were you able to get this resolved? I just bought a used MINI and I am having this problem. I was looking through the previous owner's receipts and saw that he has had the windshield replaced. Did you have to take it to the dealer and have them reset the adaptation values?

 

It turned out the sensor was not stuck the the windshield. As soon as it was applied to the windshield everything worked.