Control Module

IHKA E31 CONTROL MODULE







On E31 vehicles the IHKA control module slides into a bracket at the forward, lower portion of the IHKA housing assembly.

The module contains the electronics used to process information furnished by the system sensors, switches, and other input sources. The module also contains a non-volatile read- only-memory (ROM) where programmed operating instructions are stored.

The E31 control module has the same four 26 pin connectors, and performs the same functions as the E32 module:
- Blower speed
- Auxiliary coolant pump
- Auxiliary cooling fan
- Air intake flaps (fresh/recirculating)
- Air distribution flaps (face vent, footwell, defroster)
- Mixing flaps
- Heater core temperatures
- Evaporator temperature
- Special programmed functions
- Windshield washer spray jet heaters

Initially introduced as software version "04", version "05" was released in April 1991. Version "05" was classified as a minor redesign.

- A significant version "05" change is that, in the "up/down" air distribution mode, the defroster flaps are fully open, regardless of Y-factor, etc. This change resulted in increased air flow to the windshield to reduce the chances of window fogging.

E31 control modules are not codeable. Also, the memory is volatile; fault codes stored are erased about 4 minutes after the ignition is switched "Off".

E31 fault codes are the same as E32, except there is no Code 67 - Console outlet flap motor, since these vehicles do not have this component.