Anyone know what this is?
Discussion
It’s the humidity sensor for the climate control
From the workshop manual:
The humidity sensor is installed in a bracket attached to the inside of the windshield, to the right of the interior mirror. The sensor is concealed under a cover, which clips onto the bracket. The sensor comprises three individual elements:
A capacitive humidity sensor
A NTC thermistor air temperature sensor
An infrared windshield glass temperature sensor
.
The humidity sensor is powered by a feed from the ignition relay in the CJB. The data from the three individual elements of the humidity sensor are transmitted in LIN bus messages to the ATCM. From the data, the ATC (Automatic Temperature Control) module:
Adjusts the humidity of the air in the vehicle as necessary, to provide the optimum comfort level for occupants
Calculates the dew point temperature of the air at the inside of the windshield.
Humidity within the vehicle is controlled by raising or lowering the temperature of the evaporator. An increase in evaporator temperature increases the moisture content of the air at the windshield. Lowering the evaporator temperature reduces the moisture content of the air in the interior.
If the dew point of the air within the passenger compartment rises to be close to that of the windshield, temperature misting is likely to occur. To prevent this, the ATCM will:
Increase the blower speed
Reduce the evaporator operating temperature to its lowest safe running temperature
Increase the temperature of the air leaving the climate control assembly
Adjust the position of the demist distribution motor to direct more air to the windshield
Adjust the position of the re-circulation motor to admit more fresh air
Signal the CJB to energize the windshield heater (where fitted).
From the workshop manual:
The humidity sensor is installed in a bracket attached to the inside of the windshield, to the right of the interior mirror. The sensor is concealed under a cover, which clips onto the bracket. The sensor comprises three individual elements:
A capacitive humidity sensor
A NTC thermistor air temperature sensor
An infrared windshield glass temperature sensor
.
The humidity sensor is powered by a feed from the ignition relay in the CJB. The data from the three individual elements of the humidity sensor are transmitted in LIN bus messages to the ATCM. From the data, the ATC (Automatic Temperature Control) module:
Adjusts the humidity of the air in the vehicle as necessary, to provide the optimum comfort level for occupants
Calculates the dew point temperature of the air at the inside of the windshield.
Humidity within the vehicle is controlled by raising or lowering the temperature of the evaporator. An increase in evaporator temperature increases the moisture content of the air at the windshield. Lowering the evaporator temperature reduces the moisture content of the air in the interior.
If the dew point of the air within the passenger compartment rises to be close to that of the windshield, temperature misting is likely to occur. To prevent this, the ATCM will:
Increase the blower speed
Reduce the evaporator operating temperature to its lowest safe running temperature
Increase the temperature of the air leaving the climate control assembly
Adjust the position of the demist distribution motor to direct more air to the windshield
Adjust the position of the re-circulation motor to admit more fresh air
Signal the CJB to energize the windshield heater (where fitted).
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