IHKA Heating and Air Distribution: Notes

The Heating and Air Distribution of IHKA systems differ from the IHKS system in the following ways;

Two servomotors controlled by the IHKA module operate the temperature blend flap and air distribution mechanism. Flap position is monitored by the IHKA using potentiometers integrated in the servomotors.
A heater core sensor measures the temperature of the air coming off the heat exchanger. The sensor is located on the right side of the front of the heater unit.
A rocker switch and a power transistor (final stage) controls the blower motor at eight speeds. The blower speed is controlled manually via the rocker switch or automatically in the AUTO mode.

Fig 1: Blower Transistor Pack And Temperature Blend Flap Servo Motor

Courtesy of BMW OF NORTH AMERICA, INC.

Fig 2: IHKA Air Distribution Servo Motor

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Depending on production the date of the vehicle, the final stage unit (resistor pack) can be located as pictured above or on the blower motor assembly.