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Condensation Sensor

Condensation Sensor
The condensation sensor is new to BMW climate control systems. The sensor is used to measure air humidity and temperature in the windshield area.





This information is sent to the IHKA control unit via a digital signal with a varying frequency. This information is evaluated by the IHKA control module, which then implements a series of countermeasures to prevent windscreen fogging. The countermeasures are implemented in the following sequence:





These measures are implemented one after another until windscreen fogging is eliminated. Further steps are initiated if one measure proves to be ineffective. After successfully eliminating windscreen fogging, the measures are gradually cancelled in steps.





The sensor is located beneath the RLS on the windshield below the cover for the base of the rear view mirror. A special locating tool is used to install the new sensor, this tool is supplied with the replacement sensor. The sensor is affixed to the windscreen with an adhesive. If the sensor needs to be removed from the windshield it must be replaced.