A/C Control And Operating Unit (IHKA)

As before, the control and operating unit is the control center of the heating and air conditioning system. It is the point where all the necessary sensor data is processed and the required settings can be entered.

A new feature of the control module is that it no longer directly controls all functions and components but rather makes use of other control units for this purpose (distributed functions).

The IHKA panel is directly responsible for the following:

• SZM switch input
• Solar sensor input
• Receives the rear stratification knob (rheostat) signal
• Receives ventilation, footwell, and evaporator temperature sensor signals

The IHKA panel indirectly receives

• Condensation sensor signal via the K-CAN.

  The signal path is:

  Condensation sensor => FZD => K-CAN => IHKA

  Fig 1: Identifying A/C Control And Operating Unit

  Courtesy of BMW OF NORTH AMERICA, INC.