Functional description

The control panel for the rear air conditioner on the right is activated via the local interconnect network bus by the control unit of the rear air conditioner (HKA control unit). The locator lighting are controlled via terminal 58g by the footwell module.

In the control panel electronics of the rear air conditioner on the right the signals of the following components are detected and digitized:

• Temperature selector wheel (control panel for rear air conditioner, right)
• Temperature selector wheel (control panel for rear air conditioner, left)
• Button for the manual variation of the air supply (control panel for rear air conditioner, right)
• Button for the manual variation of the air supply (control panel for rear air conditioner, left)
• Roof air vent temperature sensor, left
• Roof air vent temperature sensor, right

The right-hand control panel on the rear air conditioner sends the signals on the LIN bus to the HKA control unit.

After the signal evaluation, the HKA control unit activates the mixing flap drives, the air distribution flap motors, the light-emitting diodes, as well as the blower of the rear air conditioner by means of an output stage.

Fig 1: Identifying Temperature Selector Wheel And LED

Courtesy of BMW OF NORTH AMERICA, INC.