Regulating Humidity

2009 Volvo C70 AutomaticSECTION Regulating Humidity
Fig 1: View Of Climate Control Modules
GLL162913Courtesy of VOLVO CARS CORPORATION

The humidity sensor checks for condensation on the windscreen. In the event of a risk of condensation, it sends a signal via serial communication to the Central electronic module (CEM) (4/56), which forwards the signal to via the CAN network to the Climate control module (CCM). Climate control module (CCM) (3/112) receives the signal and reacts as follows:

  1. Dries the incoming air by reducing the set point of the evaporator (for ECC).
  2. Starts taking in more fresh air. If the Air quality sensor (AQS) (7/159) has transmitted signals to the Climate control module (CCM) to close the fresh air damper, the Climate control module (CCM) ignores the signal and opens the fresh air damper.
  3. Transmits signals to the Damper motor module (DMM) defroster (6/102) to increase the air flow on the front windscreen.
  4. Increases the speed of the blower fan by transmitting a signal to the Central electronic module (CEM).
RENDER: 1.0x

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